This subclass aims to capture my favorite elements of the Pathfinder Alchemist in a way that is compatible with D&D Beyond, using the Rogue: Arcane Trickster as a base. Fiery bombs, poison resistance, and interesting support spells.
Rogue: Fireslinger
Some rogues get their hands on an alchemist’s fire and never look back. Fireslingers seek to bottle the inferno with a combination of science, magic and reckless creativity. Liable to spark chaos from a few unassuming vials, these rogues make excellent saboteurs and deadly ambushers.
Bonus Proficiencies
When you choose this archetype at 3rd level, you gain proficiency with alchemist’s supplies. Your proficiency bonus is doubled for any ability check you make that uses your alchemist’s supplies. In addition, you hone your aim to gain proficiency with thrown flasks such as alchemist’s fires and acid vials.
Poison Resistance
Beginning at 3rd level, your experimental alchemy grants you advantage on saving throws against poison, and resistance against poison damage.
Spellcasting
When you reach 3rd level, you learn how to infuse liquids and alchemical compounds with magical effects, in effect, bottling spells for later use. See Spells Rules for the general rules of spellcasting.
Tools Required
You produce your fireslinger spell effects with vials you prepare using your alchemist’s supplies. These vials collectively serve as your spellcasting focus, and you must have one in hand to cast any spell with this Spellcasting feature. In effect, your fireslinger spells and cantrips all have an "M" component (the vial) and an "S" component (you must have one hand free to manipulate the vial), but no "V" component (you can cast spells silently).
If a cost is indicated for a component, you must have that specific component before you can prepare that spell. If a spell states that a material component is consumed by the spell, you must provide this component for each casting of the spell. Once prepared, the vials are inert, having no effect until you are ready to cast them. Provided you have access to your alchemist’s supplies, you can prepare as many vials as you need for a given day as part of a long rest.
Bombs
Bombs are the signature spells of the fireslinger, dealing explosive elemental damage that scales with your Sneak Attack (see The Rogue Table). You prepare your bomb vials as you do your fireslinger spells. They are inert and non-explosive until you infuse them.
Cantrips
You learn three cantrips: produce flame and two other cantrips of your choice from the fireslinger spell list. You learn another fireslinger cantrip of your choice at 10th level.
Spell Slots
The Fireslinger Spellcasting table shows how many spell slots you have to cast your fireslinger spells of 1st level and higher. To cast one of these spells, you must expend a slot of the spell's level or higher. You regain all expended spell slots when you finish a long rest.
For example, if you know the 1st-level spell detect magic and have a 1st-level and a 2nd-level spell slot available, you can cast detect magic using either slot.
Spells Known of 1st Level and Higher
You know three 1st-level fireslinger spells: fire bomb and two other fireslinger spells of your choice.
The Spells Known column of the Fireslinger Spellcasting table shows when you learn more fireslinger spells of 1st level or higher. Each of these spells must be of a level for which you have spell slots. For instance, when you reach 7th level in this class, you can learn one new spell of 1st or 2nd level. Learning a new fireslinger spell requires time spent brewing with your alchemist’s supplies: at least 1 minute per spell level for the new spell.
Whenever you gain a level in this class, you can replace one of the fireslinger spells you know with another spell of your choice from the fireslinger spell list. The new spell must be of a level for which you have spell slots.
Spellcasting Ability
Intelligence is your spellcasting ability for your fireslinger spells as you develop your magic through study and experimentation (often on yourself). You use your Intelligence whenever a fireslinger spell refers to your spellcasting ability. In addition, you use your Intelligence modifier when setting the saving throw DC for a fireslinger you cast and when making an attack roll with one.
Spell save DC = 8 + your proficiency bonus + your Intelligence modifier
Spell attack modifier = your proficiency bonus + your Intelligence modifier
Fireslinger Spellcasting
Rogue
Level
Cantrips
Known
Spells
Known
— Spell Slots per Spell Level —
1st
2nd
3rd
4th
3rd
3
3
2
—
—
—
4th
3
4
3
—
—
—
5th
3
4
3
—
—
—
6th
3
4
3
—
—
—
7th
3
5
4
2
—
—
8th
3
6
4
2
—
—
9th
3
6
4
2
—
—
10th
4
7
4
3
—
—
11th
4
8
4
3
—
—
12th
4
8
4
3
—
—
13th
4
9
4
3
2
—
14th
4
10
4
3
2
—
15th
4
10
4
3
2
—
16th
4
11
4
3
3
—
17th
4
11
4
3
3
—
18th
4
11
4
3
3
—
19th
4
12
4
3
3
1
20th
4
13
4
3
3
1
Breath Weapon Bomb
At 9th level, you learn to cast a bomb as a breath weapon. As an action, you can drink the components of a bomb and expel them as a breath weapon. The breath weapon is a 15-foot cone. Each creature within the cone must make a Dexterity saving throw against your spell save DC, taking full damage as a direct hit on a failure, or half damage on a success. You must expend a spell slot of 2nd level or higher to cast a bomb as a breath weapon.
Searing Flames
At 13th level, your flames burn hot enough to harm creatures that would normally be resistant or immune. When you deal fire damage with a fireslinger spell or cantrip, you ignore resistance to fire. In addition, you can use this feature to ignore immunity to fire a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.
Delayed Blast Bomb
At 17th level, you may choose to extend the casting time of your bombs to intensify their damage. Whenever you cast a bomb, you may choose to cast it as a concentration spell with a duration of 1 minute. When the spell ends, either because your concentration is broken or because you decide to end it, the vial explodes. If at the end of your turn, the bomb has not yet detonated, the damage increases by 1d6.
If a creature other than you touches the vial before the interval has expired, that creature must make a Dexterity saving throw. On a failed save, the spell ends immediately, causing the vial to explode and dealing damage as to that creature as though it was the target of the spell. On a successful save, the creature can throw the vial up to 20 feet. When it strikes a creature or a solid object, the spell ends, and the vial explodes.
Fireslinger Spell List
Homebrew spells are marked with an * and are detailed in the New Spells section.
Cantrips
Acid Splash, Blade Ward, Control Flames, Create Bonfire, Dancing Lights, Fire Bolt, Frostbite, Mold Earth, Poison Spray, Produce Flame, Ray of Frost, Smokescreen*, Spare the Dying, True Strike
1st Level
Absorb Elements, Cure Wounds, Detect Magic, Detect Poison and Disease, Disguise Self, Expeditious Retreat, False Life, Feather Fall, Fire Bomb*, Fog Cloud, Heroism, Identify, Jump, Longstrider, Protection from Evil and Good, Purify Food and Drink, Sanctuary, Sandstone Solution*, Sleep
2nd Level
Alter Self, Barkskin, Blindness/Deafness, Blur, Continual Flame, Darkvision, Detect Thoughts, Enhance Ability, Enlarge/Reduce, Hold Person, Invisibility, Levitate, Lesser Restoration, Protection from Poison, See Invisibility, Silence, Spider Climb
3rd Level
Blink, Clairvoyance, Feign Death, Elemental Weapon, Fly, Gaseous Form, Haste, Intellect Fortress, Meld Into Stone, Protection from Energy, Remove Curse, Stinking Cloud, Water Breathing, Water Walk
4th Level
Arcane Eye, Blight, Control Water, Death Ward, Elemental Bane, Fire Shield, Freedom of Movement, Greater Invisibility, Stoneskin, Stone Shape, Wall of Fire
New Spells
Fire Bomb
1st-level evocation Casting Time: 1 action Range: 60 feet Components: S, M (a small piece of phosphorus) Duration: Instantaneous
You hurl a fiery vial at a creature or object within range. Make a ranged spell attack against the target. On a hit, the target takes 1d6 fire damage plus bonus damage equal to your intelligence modifier. Each other creature within 5 feet of the target must make a Dexterity saving throw against your spell save DC, taking full damage on a failed save, or half damage on a success.
The amount of damage increases as you gain levels in the Rogue class, as shown in the Sneak Attack column of The Rogue Table.
Sandstone Solution
1st-level transmutation Casting Time: 1 action Range: Touch Components: S, M (a drop of vinegar) Duration: 1 minute
You apply a cloudy solution to a surface causing a five-foot cube of sand or dirt to become hard as stone or a five-foot cube of stone to become soft and crumbly. This effect lasts for 1 minute.
Smokescreen
Conjuration cantrip Casting Time: 1 action Range: 20 feet Components: S, M (a smoke pellet) Duration: 1 round
You create a cloud of dense smoke that fills a 5-foot space in range. The area is heavily obscured. It lasts until the end of your next turn, or until a wind of moderate or greater speed (at least 10 miles per hour) disperses it.
I'd appreciate feedback on this subclass, especially Fire Bomb which is the cornerstone of it. It's based on the Pathfinder Alchemist class/Bomb feature. In short, fireslingers get fewer bombs with better range and splash damage, but they're harder to hit with and fail completely on a miss. And with their limited 1/3 caster spell slots, they have to choose between Fire Bomb and any other spell they might want to cast.
Pathfinder Alchemist Bomb feature
Bombs per day: Class level + Intelligence modifier times per day. Does not consume a spell slot.
Spell slots: roughly 1/2 caster equivalent.
Attack bonus: Uses the "Throw Splash Weapon", which completely disregards the AC bonus from the target's armor, natural armor, or shield.
Damage to target: 1d6 Fire Damage + bonus damage equal to Intelligence modifier; scales up with same progression as Rogue's Sneak Attack.
Critical hit: Only the initial 1d6 fire damage is doubled, not the additional d6s from leveling up, same as how Sneak Attack works in Pathfinder.
Splash damage: Creatures within 5-feet of the target must make a Dexterity saving throw or take damage equal to the minimum bomb damage (or half of the minimum on a successful save).
Range: 20ft
Effect on a miss: No one takes a direct hit. Target space shifts by one in a random direction to determine who gets hit for splash damage.
At 3rd level: 3 + Intelligence modifier times per day; 2d6 + Intelligence modifier fire damage.
At 20th level: 20 + Intelligence modifier times per day; 10d6 + Intelligence modifier fire damage.
Changes for this subclass
Bombs per day: Uses a 1st level spell slot (no benefit from upcasting); approximately halved from Pathfinder if the fireslinger spends every spell slot on Fire Bomb, or even less if they want to use their other spells.
Spell slots: 1/3 caster as per Arcane Trickster; fewer slots.
Attack bonus: Ranged spell attack (Intelligence) with proficiency; doesn't ignore armor, so harder to land a hit with.
Damage to target: 1d6 Fire Damage + bonus damage equal to Intelligence modifier; scales up with same progression as Rogue's Sneak Attack.
Critical hit: All d6s are doubled, same as how Sneak Attack works in DnD.
Splash damage: Creatures within 5-feet of the target must make a Dexterity saving throw, taking full damage on a failure, or half damage on a success; beneficial when enemies are in splash radius, but detrimental when allies are in splash radius; I made this change because DnD doesn't seem to use minimum damage as a mechanic.
Range: 60ft (increased range to make it less likely for allies to be in splash radius).
Effect on a miss: Spell fails, no damage; wastes spell slot, but poses no risk to allies.
At 3rd level: Up to 2 times per day; 2d6 + Intelligence modifier fire damage.
At 20th level: Up to 11 times per day; 10d6 + Intelligence modifier fire damage.
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Currently homebrewing the Mistveil Rogue, an elusive infiltrator that can vanish into thin air.
So this feature is essentially a fire version of ice knife, and I'd recommend you have it work the same way - minor damage for hitting the primary target plus area damage when the bomb explodes. This model never results in zero damage unless you miss your attack and everyone makes the save. I think this would be more fun than having zero effect on a miss.
I think spell slots are the wrong resource for this. The point of spell slots is that they are an automatically-scaling resource, but by ignoring spell level and scaling by rogue level instead you are essentially just using spell slots as "you get X number of bombs per day." If that's your goal, just give them X uses and call it a day. Using spell slots isn't providing any additional functionality and requires you to have the counterintuitive disclaimer that spell level should be disregarded.
And as long as we're making these not-spells, throwing a physical bomb feels a lot more like a dexterity-based ranged weapon attack than an intelligence-based spell attack. It also lets the rogue be a rogue instead of being torn between a DEX or INT focus.
I guess ultimately I wouldn't use Arcane Trickster as a base. I get that it's more equivalent to the PF Alchemist design, but I don't think its actually doing you any favors as a guide to porting this over.
Thanks for your feedback! I did use ice knife as a reference, and I've gone back and forth over primary target vs area damage. I wanted to keep the bonus damage from the Intelligence modifier, so I picked that over say, primary bludgeoning damage from being hit with the vial. Or piercing, perhaps, from exploding glass.
Although zero damage on a miss is annoying, I thought it would counterbalance the area damage - on a lucky bomb with several enemies in 5 feet of the target, you would effectively get AoE Sneak Attack fire damage against all of them, which seems very powerful when there's no other Rogue subclass that lets you Sneak Attack more than once in a turn. (On a related note, I couldn't decide whether to disallow normal Sneak Attack damage on the same turn as you use a Fire Bomb - thoughts?)
As for spell slots - a spell can use only one kind of scaling damage, so I used character level to make Fire Bomb scale like Sneak Attack. This meant I couldn't use spell slot scaling, so that's why there's no benefit to upcasting Fire Bomb. But the Fireslinger Spell List is an interesting mix of spells, including a couple of cleric spells a Rogue wouldn't normally get access to, so there are other ways to use those spell slots, including on spells that do benefit from upcasting.
On the first draft, I had spell slots for spells, and a separate counter for bombs - it's interesting, a lot of your feedback steers it back towards where I started with this subclass! But with the potential for AoE Sneak Attack seeming quite powerful, I thought spell slots + bombs was maybe too powerful. But if it's not OP, I could separate them out again - how many X per long rest, do you think?
The DEX/INT split was intentional to prevent the subclass being too single-ability dependent - dealing decent fire damage, but you have to invest in intelligence for bonus damage and for spell save DC.
Bombs as a ranged weapon - my first draft had that, range 20/60 like darts or thrown daggers. But it wasn't possible to make the attack dexterity-based while also applying intelligence-based bonus damage.
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Currently homebrewing the Mistveil Rogue, an elusive infiltrator that can vanish into thin air.
How many times should a fireslinger be able to bomb per long rest?
Is 15-foot diameter sphere AoE sneak attack fire damage okay (limited use)?
Is the preferred AoE notation 15-foot sphere, or target plus all creatures within 5 feet of the target (like ice knife?
Is it OP to replace all fireslinger spell components with S, M, but no V? I.e. you must have a free hand and materials for your spells, but you can cast in silence?
Thinking about how Rogue subclasses function, they tend to grant two things - a way to get more sneak attack damage, and something else useful. Arcane Tricksters get spells that enable sneak attacks, and gain spellcasting. Specifically, Mage Hand is a cantrip, so an Arcane Trickster can use it an unlimited number of times per long rest.
The Fireslinger can deal sneak attack fire damage as a ranged AoE x times per day, and gain alchemy-themed spellcasting. The damage has an AoE which Arcane Trickster's doesn't, so I think it needs to be limited to x times per long rest. But what should x be?
The Pathfinder x seems too high: class level + Intelligence modifier would cap at something like 23 per long rest at level 20 (10d6 damage each for 230d6), compared to a wizard who would cast Fireball 15 times per long rest at level 20 (8d6 minimum damage to 16d6 maximum damage = 243d6). Similar number of times and number of dice, but wizard has a much larger range and AoE.
Half class level + Intelligence modifier could work, it would cap at something like 13 at level 20.
Bombs needing spell slots is similar, but slightly less than half class level + Intelligence modifier.
Alternatively, should I remove the AoE and the number of times limitation, so it becomes you can do ranged fire damage sneak attacks to a single target as many times as you want, provided you can hit? Like a subclass-specific cantrip.
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Currently homebrewing the Mistveil Rogue, an elusive infiltrator that can vanish into thin air.
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This subclass aims to capture my favorite elements of the Pathfinder Alchemist in a way that is compatible with D&D Beyond, using the Rogue: Arcane Trickster as a base. Fiery bombs, poison resistance, and interesting support spells.
Rogue: Fireslinger
Some rogues get their hands on an alchemist’s fire and never look back. Fireslingers seek to bottle the inferno with a combination of science, magic and reckless creativity. Liable to spark chaos from a few unassuming vials, these rogues make excellent saboteurs and deadly ambushers.
Bonus Proficiencies
When you choose this archetype at 3rd level, you gain proficiency with alchemist’s supplies. Your proficiency bonus is doubled for any ability check you make that uses your alchemist’s supplies. In addition, you hone your aim to gain proficiency with thrown flasks such as alchemist’s fires and acid vials.
Poison Resistance
Beginning at 3rd level, your experimental alchemy grants you advantage on saving throws against poison, and resistance against poison damage.
Spellcasting
When you reach 3rd level, you learn how to infuse liquids and alchemical compounds with magical effects, in effect, bottling spells for later use. See Spells Rules for the general rules of spellcasting.
Tools Required
You produce your fireslinger spell effects with vials you prepare using your alchemist’s supplies. These vials collectively serve as your spellcasting focus, and you must have one in hand to cast any spell with this Spellcasting feature. In effect, your fireslinger spells and cantrips all have an "M" component (the vial) and an "S" component (you must have one hand free to manipulate the vial), but no "V" component (you can cast spells silently).
If a cost is indicated for a component, you must have that specific component before you can prepare that spell. If a spell states that a material component is consumed by the spell, you must provide this component for each casting of the spell. Once prepared, the vials are inert, having no effect until you are ready to cast them. Provided you have access to your alchemist’s supplies, you can prepare as many vials as you need for a given day as part of a long rest.
Bombs
Bombs are the signature spells of the fireslinger, dealing explosive elemental damage that scales with your Sneak Attack (see The Rogue Table). You prepare your bomb vials as you do your fireslinger spells. They are inert and non-explosive until you infuse them.
Cantrips
You learn three cantrips: produce flame and two other cantrips of your choice from the fireslinger spell list. You learn another fireslinger cantrip of your choice at 10th level.
Spell Slots
The Fireslinger Spellcasting table shows how many spell slots you have to cast your fireslinger spells of 1st level and higher. To cast one of these spells, you must expend a slot of the spell's level or higher. You regain all expended spell slots when you finish a long rest.
For example, if you know the 1st-level spell detect magic and have a 1st-level and a 2nd-level spell slot available, you can cast detect magic using either slot.
Spells Known of 1st Level and Higher
You know three 1st-level fireslinger spells: fire bomb and two other fireslinger spells of your choice.
The Spells Known column of the Fireslinger Spellcasting table shows when you learn more fireslinger spells of 1st level or higher. Each of these spells must be of a level for which you have spell slots. For instance, when you reach 7th level in this class, you can learn one new spell of 1st or 2nd level. Learning a new fireslinger spell requires time spent brewing with your alchemist’s supplies: at least 1 minute per spell level for the new spell.
Whenever you gain a level in this class, you can replace one of the fireslinger spells you know with another spell of your choice from the fireslinger spell list. The new spell must be of a level for which you have spell slots.
Spellcasting Ability
Intelligence is your spellcasting ability for your fireslinger spells as you develop your magic through study and experimentation (often on yourself). You use your Intelligence whenever a fireslinger spell refers to your spellcasting ability. In addition, you use your Intelligence modifier when setting the saving throw DC for a fireslinger you cast and when making an attack roll with one.
Spell save DC = 8 + your proficiency bonus + your Intelligence modifier
Spell attack modifier = your proficiency bonus + your Intelligence modifier
Fireslinger Spellcasting
Rogue
Level
Cantrips
Known
Spells
Known
— Spell Slots per Spell Level —
1st
2nd
3rd
4th
3rd
3
3
2
—
—
—
4th
3
4
3
—
—
—
5th
3
4
3
—
—
—
6th
3
4
3
—
—
—
7th
3
5
4
2
—
—
8th
3
6
4
2
—
—
9th
3
6
4
2
—
—
10th
4
7
4
3
—
—
11th
4
8
4
3
—
—
12th
4
8
4
3
—
—
13th
4
9
4
3
2
—
14th
4
10
4
3
2
—
15th
4
10
4
3
2
—
16th
4
11
4
3
3
—
17th
4
11
4
3
3
—
18th
4
11
4
3
3
—
19th
4
12
4
3
3
1
20th
4
13
4
3
3
1
Breath Weapon Bomb
At 9th level, you learn to cast a bomb as a breath weapon. As an action, you can drink the components of a bomb and expel them as a breath weapon. The breath weapon is a 15-foot cone. Each creature within the cone must make a Dexterity saving throw against your spell save DC, taking full damage as a direct hit on a failure, or half damage on a success. You must expend a spell slot of 2nd level or higher to cast a bomb as a breath weapon.
Searing Flames
At 13th level, your flames burn hot enough to harm creatures that would normally be resistant or immune. When you deal fire damage with a fireslinger spell or cantrip, you ignore resistance to fire. In addition, you can use this feature to ignore immunity to fire a number of times equal to your proficiency bonus, and you regain all expended uses when you finish a long rest.
Delayed Blast Bomb
At 17th level, you may choose to extend the casting time of your bombs to intensify their damage. Whenever you cast a bomb, you may choose to cast it as a concentration spell with a duration of 1 minute. When the spell ends, either because your concentration is broken or because you decide to end it, the vial explodes. If at the end of your turn, the bomb has not yet detonated, the damage increases by 1d6.
If a creature other than you touches the vial before the interval has expired, that creature must make a Dexterity saving throw. On a failed save, the spell ends immediately, causing the vial to explode and dealing damage as to that creature as though it was the target of the spell. On a successful save, the creature can throw the vial up to 20 feet. When it strikes a creature or a solid object, the spell ends, and the vial explodes.
Fireslinger Spell List
Homebrew spells are marked with an * and are detailed in the New Spells section.
Cantrips
Acid Splash, Blade Ward, Control Flames, Create Bonfire, Dancing Lights, Fire Bolt, Frostbite, Mold Earth, Poison Spray, Produce Flame, Ray of Frost, Smokescreen*, Spare the Dying, True Strike
1st Level
Absorb Elements, Cure Wounds, Detect Magic, Detect Poison and Disease, Disguise Self, Expeditious Retreat, False Life, Feather Fall, Fire Bomb*, Fog Cloud, Heroism, Identify, Jump, Longstrider, Protection from Evil and Good, Purify Food and Drink, Sanctuary, Sandstone Solution*, Sleep
2nd Level
Alter Self, Barkskin, Blindness/Deafness, Blur, Continual Flame, Darkvision, Detect Thoughts, Enhance Ability, Enlarge/Reduce, Hold Person, Invisibility, Levitate, Lesser Restoration, Protection from Poison, See Invisibility, Silence, Spider Climb
3rd Level
Blink, Clairvoyance, Feign Death, Elemental Weapon, Fly, Gaseous Form, Haste, Intellect Fortress, Meld Into Stone, Protection from Energy, Remove Curse, Stinking Cloud, Water Breathing, Water Walk
4th Level
Arcane Eye, Blight, Control Water, Death Ward, Elemental Bane, Fire Shield, Freedom of Movement, Greater Invisibility, Stoneskin, Stone Shape, Wall of Fire
New Spells
Fire Bomb
1st-level evocation
Casting Time: 1 action
Range: 60 feet
Components: S, M (a small piece of phosphorus)
Duration: Instantaneous
You hurl a fiery vial at a creature or object within range. Make a ranged spell attack against the target. On a hit, the target takes 1d6 fire damage plus bonus damage equal to your intelligence modifier. Each other creature within 5 feet of the target must make a Dexterity saving throw against your spell save DC, taking full damage on a failed save, or half damage on a success.
The amount of damage increases as you gain levels in the Rogue class, as shown in the Sneak Attack column of The Rogue Table.
Sandstone Solution
1st-level transmutation
Casting Time: 1 action
Range: Touch
Components: S, M (a drop of vinegar)
Duration: 1 minute
You apply a cloudy solution to a surface causing a five-foot cube of sand or dirt to become hard as stone or a five-foot cube of stone to become soft and crumbly. This effect lasts for 1 minute.
Smokescreen
Conjuration cantrip
Casting Time: 1 action
Range: 20 feet
Components: S, M (a smoke pellet)
Duration: 1 round
You create a cloud of dense smoke that fills a 5-foot space in range. The area is heavily obscured. It lasts until the end of your next turn, or until a wind of moderate or greater speed (at least 10 miles per hour) disperses it.
Currently homebrewing the Mistveil Rogue, an elusive infiltrator that can vanish into thin air.
I'd appreciate feedback on this subclass, especially Fire Bomb which is the cornerstone of it. It's based on the Pathfinder Alchemist class/Bomb feature. In short, fireslingers get fewer bombs with better range and splash damage, but they're harder to hit with and fail completely on a miss. And with their limited 1/3 caster spell slots, they have to choose between Fire Bomb and any other spell they might want to cast.
Pathfinder Alchemist Bomb feature
Bombs per day: Class level + Intelligence modifier times per day. Does not consume a spell slot.
Spell slots: roughly 1/2 caster equivalent.
Attack bonus: Uses the "Throw Splash Weapon", which completely disregards the AC bonus from the target's armor, natural armor, or shield.
Damage to target: 1d6 Fire Damage + bonus damage equal to Intelligence modifier; scales up with same progression as Rogue's Sneak Attack.
Critical hit: Only the initial 1d6 fire damage is doubled, not the additional d6s from leveling up, same as how Sneak Attack works in Pathfinder.
Splash damage: Creatures within 5-feet of the target must make a Dexterity saving throw or take damage equal to the minimum bomb damage (or half of the minimum on a successful save).
Range: 20ft
Effect on a miss: No one takes a direct hit. Target space shifts by one in a random direction to determine who gets hit for splash damage.
At 3rd level: 3 + Intelligence modifier times per day; 2d6 + Intelligence modifier fire damage.
At 20th level: 20 + Intelligence modifier times per day; 10d6 + Intelligence modifier fire damage.
Changes for this subclass
Bombs per day: Uses a 1st level spell slot (no benefit from upcasting); approximately halved from Pathfinder if the fireslinger spends every spell slot on Fire Bomb, or even less if they want to use their other spells.
Spell slots: 1/3 caster as per Arcane Trickster; fewer slots.
Attack bonus: Ranged spell attack (Intelligence) with proficiency; doesn't ignore armor, so harder to land a hit with.
Damage to target: 1d6 Fire Damage + bonus damage equal to Intelligence modifier; scales up with same progression as Rogue's Sneak Attack.
Critical hit: All d6s are doubled, same as how Sneak Attack works in DnD.
Splash damage: Creatures within 5-feet of the target must make a Dexterity saving throw, taking full damage on a failure, or half damage on a success; beneficial when enemies are in splash radius, but detrimental when allies are in splash radius; I made this change because DnD doesn't seem to use minimum damage as a mechanic.
Range: 60ft (increased range to make it less likely for allies to be in splash radius).
Effect on a miss: Spell fails, no damage; wastes spell slot, but poses no risk to allies.
At 3rd level: Up to 2 times per day; 2d6 + Intelligence modifier fire damage.
At 20th level: Up to 11 times per day; 10d6 + Intelligence modifier fire damage.
Currently homebrewing the Mistveil Rogue, an elusive infiltrator that can vanish into thin air.
So this feature is essentially a fire version of ice knife, and I'd recommend you have it work the same way - minor damage for hitting the primary target plus area damage when the bomb explodes. This model never results in zero damage unless you miss your attack and everyone makes the save. I think this would be more fun than having zero effect on a miss.
I think spell slots are the wrong resource for this. The point of spell slots is that they are an automatically-scaling resource, but by ignoring spell level and scaling by rogue level instead you are essentially just using spell slots as "you get X number of bombs per day." If that's your goal, just give them X uses and call it a day. Using spell slots isn't providing any additional functionality and requires you to have the counterintuitive disclaimer that spell level should be disregarded.
And as long as we're making these not-spells, throwing a physical bomb feels a lot more like a dexterity-based ranged weapon attack than an intelligence-based spell attack. It also lets the rogue be a rogue instead of being torn between a DEX or INT focus.
I guess ultimately I wouldn't use Arcane Trickster as a base. I get that it's more equivalent to the PF Alchemist design, but I don't think its actually doing you any favors as a guide to porting this over.
My homebrew subclasses (full list here)
(Artificer) Swordmage | Glasswright | (Barbarian) Path of the Savage Embrace
(Bard) College of Dance | (Fighter) Warlord | Cannoneer
(Monk) Way of the Elements | (Ranger) Blade Dancer
(Rogue) DaggerMaster | Inquisitor | (Sorcerer) Riftwalker | Spellfist
(Warlock) The Swarm
Thanks for your feedback! I did use ice knife as a reference, and I've gone back and forth over primary target vs area damage. I wanted to keep the bonus damage from the Intelligence modifier, so I picked that over say, primary bludgeoning damage from being hit with the vial. Or piercing, perhaps, from exploding glass.
Although zero damage on a miss is annoying, I thought it would counterbalance the area damage - on a lucky bomb with several enemies in 5 feet of the target, you would effectively get AoE Sneak Attack fire damage against all of them, which seems very powerful when there's no other Rogue subclass that lets you Sneak Attack more than once in a turn. (On a related note, I couldn't decide whether to disallow normal Sneak Attack damage on the same turn as you use a Fire Bomb - thoughts?)
As for spell slots - a spell can use only one kind of scaling damage, so I used character level to make Fire Bomb scale like Sneak Attack. This meant I couldn't use spell slot scaling, so that's why there's no benefit to upcasting Fire Bomb. But the Fireslinger Spell List is an interesting mix of spells, including a couple of cleric spells a Rogue wouldn't normally get access to, so there are other ways to use those spell slots, including on spells that do benefit from upcasting.
On the first draft, I had spell slots for spells, and a separate counter for bombs - it's interesting, a lot of your feedback steers it back towards where I started with this subclass! But with the potential for AoE Sneak Attack seeming quite powerful, I thought spell slots + bombs was maybe too powerful. But if it's not OP, I could separate them out again - how many X per long rest, do you think?
The DEX/INT split was intentional to prevent the subclass being too single-ability dependent - dealing decent fire damage, but you have to invest in intelligence for bonus damage and for spell save DC.
Bombs as a ranged weapon - my first draft had that, range 20/60 like darts or thrown daggers. But it wasn't possible to make the attack dexterity-based while also applying intelligence-based bonus damage.
Currently homebrewing the Mistveil Rogue, an elusive infiltrator that can vanish into thin air.
Questions for developing this:
Thinking about how Rogue subclasses function, they tend to grant two things - a way to get more sneak attack damage, and something else useful. Arcane Tricksters get spells that enable sneak attacks, and gain spellcasting. Specifically, Mage Hand is a cantrip, so an Arcane Trickster can use it an unlimited number of times per long rest.
The Fireslinger can deal sneak attack fire damage as a ranged AoE x times per day, and gain alchemy-themed spellcasting. The damage has an AoE which Arcane Trickster's doesn't, so I think it needs to be limited to x times per long rest. But what should x be?
The Pathfinder x seems too high: class level + Intelligence modifier would cap at something like 23 per long rest at level 20 (10d6 damage each for 230d6), compared to a wizard who would cast Fireball 15 times per long rest at level 20 (8d6 minimum damage to 16d6 maximum damage = 243d6). Similar number of times and number of dice, but wizard has a much larger range and AoE.
Half class level + Intelligence modifier could work, it would cap at something like 13 at level 20.
Bombs needing spell slots is similar, but slightly less than half class level + Intelligence modifier.
Alternatively, should I remove the AoE and the number of times limitation, so it becomes you can do ranged fire damage sneak attacks to a single target as many times as you want, provided you can hit? Like a subclass-specific cantrip.
Currently homebrewing the Mistveil Rogue, an elusive infiltrator that can vanish into thin air.