One spell that can be great for an Arcane Trickster is Shadow Blade. Sure, you don't add your modifier to damage, but you get advantage on attack rolls with the blade made in dim light or darkness AND the damage is all psychic damage. So if you Sneak Attack with it at 9th level (when you can learn the spell), that's 2d8+5d6 psychic damage.
Another minor plus for this is that Shadow Blade is an Illusion spell, so it doesn't take up one of your precious non-trickstery spells
One spell that can be great for an Arcane Trickster is Shadow Blade. Sure, you don't add your modifier to damage, but you get advantage on attack rolls with the blade made in dim light or darkness AND the damage is all psychic damage. So if you Sneak Attack with it at 9th level (when you can learn the spell), that's 2d8+5d6 psychic damage.
Another minor plus for this is that Shadow Blade is an Illusion spell, so it doesn't take up one of your precious non-trickstery spells
You get your dex (or str if you prefer) mod to attack and damage with the shadow blade, it is effectively a normal melee weapon that does 2d8 psychic for its damage dice.
Correct. You get Shadow Blade at level 7, and you can add dexterity or strength to the damage.
I've found that Minor Illusion + Mage Hand is a great way to open a door. You use minor illusion to create a hiding place for yourself 30ft away from the door, and then you use your invisible Mage Hand to open the door. If the enemies in the room have heard the combat going on nearby, it's not unreasonable for the DM to have them readying an action to attack whoever opens the door. It's very videogamey and unrealistic for enemies to be completely oblivious to combat going on less than 100ft away just because it's on the other side of a closed door. If they didn't come rushing out to help, they're probably planning to ambush whoever opens the door.
If you're using the Booming Blade cantrip, expect your DM to consider combat to be quite loud. Even without using that spell or other loud spells, expect combat to be pretty loud. Especially if your players are trying to communicate to each other during combat. Booming Blade is an awesome cantrip, but it can cause the DM to send waves of enemies at you, instead of you getting to come to them.
Another trick with minor illusion / silent image is making a replica of an opening. For instance you are exiting a cave but scout ahead and see a bunch of goblins ready to ambush you. So you create an illusion of the cave mouth itself. That way the goblins can’t think they are still looking at the cave mouth entrance but your party is sneaky slowly up behind it. Once your party member said touch it they auto-see through the illusion while the goblins are most likely unaware of anything other than the normal cave opening.
I'm currently playing an Arcane Trickster and my suggestion would be to avoid using one of your precious few cantrips on Firebolt or any of the ranged attack cantrips. I highly suggest Booming Blade, Minor Illusion, and Mage Hand to start off. The thing about ranged attack spells is that you can just use a Hand Crossbow and keep your sneak attack damage and be using your primary attribute of Dex, which is what you'll most likely be increasing over time. Booming blade is great because it works with your dex and your sneak attack, but otherwise, I suggest using cantrips, which you cannot change later, for things that will give you the greatest utility. Booming blade is the only attack cantrip you need and minor illusion is incredibly useful.
For first level spells, I took Find Familiar, Silent Image, Disguise Self and Charm Person. Really good spells, but I'm yet to find a use for Charm Person. I think it's great, but extremely situational and I'll probably temporarily give it up when I get access to 2nd level spells (I'm level 5). For find familiar, I use a Tressym. Owl is optimal, but Tressym's ability to see invisible things has saved us some pain. Any familiar that can be there to grant you that sneak attack is a solid choice. The Dodge action is their friend if they aren't an Owl. Barding to up their AC if you are allowed.
For second level spells, I don't have them yet, but I'm looking closely at Invisibility and Mirror Image. Shadow Blade is good too, as it works well with your rogue abilities and scales. It's concentration, so that's yet another point in Mirror image's favor over Blur. Mirror Image will help you keep Shadow Blade going, but remember that even though one is a bonus action, you cant cast both in one turn. This is when you start to wish you had Shield after all, despite Uncanny Dodge.
I agree with your comment about using one of your precious Cantrip slots on a ranged spell attack cantrip. It's such a waste when there are so many good options there instead.
Mage Hand is required, so you only get two choices for cantrips until you get a 3rd choice at level 10. It's best to take one melee attack cantrip and one utility cantrip with these two cantrip choices.
Message is a great cantrip if you're acting as the party scout. Control Flames is useful if you're trying to fight in the dark. These two cantrips have very specific uses, but these can be uses that are both important and frequent, despite being so specific. On the other hand, Minor Illusion is incredibly useful and can be used for such a wide variety of purposes. Prestidigitation is also a cantrip which can be used in such a huge range of situations.
Booming Blade is better than Green Flame Blade most of the time, but it's acceptable to take Green Flame Blade instead of Booming Blade (primarily if you want to stay somewhat sneaky in combat). If you're going to be at level 5+, it's pretty important to have taken either Booming Blade or Green Flame Blade. Without it, you'll have such a low amount of damage on the turns when you aren't able to get sneak attack.
A kenku(preferably) or variant human(with actor feat), disguise self(cannot easily discern you aren't the same person), silent image(kenku uses voice to create sounds and voices), definitely grab find familiar, maybe dip into warlock 2 for infinite disguise self's and other utility? Like devil's sight + extra spells.
I think I took fire bolt and friends as my cantrips. Which sucks since I barely use them and this was one of my first 5th edition characters. (My next was a hexblade and I took true strike... I didn't learn.) But, I did get minor illusion from my tiefling variant and multiclassed into bard for predidgitation and vicious mockery. I am mostly using my bow to deal damage so booming blade and green flame blade wouldn't help me much anyway.
For my non illusion/enchantment spell I took shield which is coming in pretty handy since I only have a 16 AC and sometimes uncanny dodge just doesn't cut it, however, absorb elements may be able to protect me better against things that shield and uncanny dodge cannot.
One spell I have yet to see in this thread that's surprisingly excellent for Tricksters is Catapult.
Catapult allows you to select one object weighing between one to five pounds anywhere within sixty feet, and cause it to rocket ninety feet in any direction you choose. You can 'shoot' people with it, forcing the first critter in the line of motion to make a Dex save or suffer 3d8 bludgeoning damage (some DMs will be willing to negotiate on this for items such as "Flask of acid", so keep that in mind!). Upcasting the spell gives you an extra five pounds of weight you can Catapult (so 10 pounds for a level 2, 15lbs for level 3, and so forth), as well as an extra 1d8 bludgeoning damage.
"Why is this weird girl yammering on about a spell that lets you improvise basic bludgeoning damage like a nerd instead of cool illusion spells?" you ask?
Catapult requires nothing but somatic components. No verbal, no material. Nothing but somatic.
Post up in a good hiding spot (or make one with Minor Illusion) and prepare your Poltergeist show as random items in wherever you are fly in directions you choose. You can spook superstitious things or frighten animals - or, if you target a log in a fireplace, you can start a fire without anyone else being the wiser as to your location. Get Magical Ambush at 9th level and you can impose disadvantage on any given critter's save vs. telekinetic bullhonkey, and again - no verbal components, no material components, no flash or spectacle.
One item within sixty feet of you flies at damaging velocity ninety feet in a straight line, and unless you give the game away some other way, your Trickster remains perfectly hidden and ready to do it again, or to take advantage of the confusion Ork McGork's face suddenly being covered in alchemist's fire causes to start with the crossbow bolts.
Catapult. It's better than you think it is for Tricksters.
Also, I think Shadow Blade is very good, 2d8+dex, advantage if in darkness or dim light(perfect for rogues), if with advantage, sneak attack. Incredibly useful if your Dm allows you to stack advantages.
I think I took fire bolt and friends as my cantrips. Which sucks since I barely use them and this was one of my first 5th edition characters. (My next was a hexblade and I took true strike... I didn't learn.) But, I did get minor illusion from my tiefling variant and multiclassed into bard for predidgitation and vicious mockery. I am mostly using my bow to deal damage so booming blade and green flame blade wouldn't help me much anyway.
For my non illusion/enchantment spell I took shield which is coming in pretty handy since I only have a 16 AC and sometimes uncanny dodge just doesn't cut it, however, absorb elements may be able to protect me better against things that shield and uncanny dodge cannot.
Multiclassing for vicious mockery for someone who has both firebolt and a bow is an unusual choice. I'd be hesitant to slow down my spell and sneak attack progression without a really good reason. In my opinion, you should have taken either of the ranged damage cantrips. Unless you hate using sneak attack for some reason, just use your bow.
I will say that Friends is an okay pick if you also take Disguise Self. In combination, it will leave them angry with someone else.
The only real use I've ever found for Prestidigitation is cleaning things really well, but I know people talk about how useful it is. I'm yet to see it.
A kenku(preferably) or variant human(with actor feat), disguise self(cannot easily discern you aren't the same person), silent image(kenku uses voice to create sounds and voices), definitely grab find familiar, maybe dip into warlock 2 for infinite disguise self's and other utility? Like devil's sight + extra spells.
I think Half-elf is a great race for the Arcane Trickster too. I find that talking is an important part of what most Tricksters get up to and you get 8 skills. I personally wouldn't multiclass into a warlock, but if you did, you could take beguiling influence and have 10 skills. Skills are kind of a big deal for rogues and a rogue with high intelligence, dexterity, and charisma can be really good at a lot of different things that aid in an Arcane Trickster lifestyle.
Also, I think Shadow Blade is very good, 2d8+dex, advantage if in darkness or dim light(perfect for rogues), if with advantage, sneak attack. Incredibly useful if your Dm allows you to stack advantages.
I never have issue getting advantage. Between a familiar, hiding, and teammates I'm good. Bonus action hide tends to work well in dim light or darkness to begin with. The extra 1d8 is fine, but loses it's appeal quickly if you have a magical weapon(which you usually have by 7th level). It's also concentration for a melee spell on a character with no proficiency in con saves, a relatively low AC and few spell slots. A +1 Rapier and a different spell choice will likely be the route I take. I would take Shadow Blade for a Crit Fisher maybe, but i'd make sure to have Mirror Image and Shield or some other additional defense prepared to keep the spell up. You will get hit.
One spell I have yet to see in this thread that's surprisingly excellent for Tricksters is Catapult.
Catapult allows you to select one object weighing between one to five pounds anywhere within sixty feet, and cause it to rocket ninety feet in any direction you choose. You can 'shoot' people with it, forcing the first critter in the line of motion to make a Dex save or suffer 3d8 bludgeoning damage (some DMs will be willing to negotiate on this for items such as "Flask of acid", so keep that in mind!). Upcasting the spell gives you an extra five pounds of weight you can Catapult (so 10 pounds for a level 2, 15lbs for level 3, and so forth), as well as an extra 1d8 bludgeoning damage.
Interesting. I'd worry about having enough things to use. I imagine there wont always be something present at your location, which means possibly carrying numerous various weights of objects to use as ammunition. While a hilarious idea and pretty decent damage, there are some issues even if you don't have any with finding or carrying ammunition. One is that the damage is roughly the same as just sneak attacking with a hand crossbow when you get the spell and it doesn't compare to sneak attack so well as you level. Another is that the weight and distance limit keeps you from doing so many fun things you might think of with it. I personally prefer a damage type more exotic than bludgeoning on an attack spell, since spells are good to resort to when traditional weapons don't work well. You are more likely to want to increase your dexterity than intelligence early on too, so a spell they may resist eating a spell slot in the attempt is fine, but not great with a little bit of a lower save for a while.The last thing is that it takes your precious spot for a non-enchantment, non-illusion spell (so many good choices). With damage that weak, I'm not sure if the hilarity is worthy it. You can get advantage on your hand crossbow attacks right out of the gate too. This is all purely optimization talk. It seems maybe good against low dex heavily armored opponents and have some fun utility though. In the end, the best spell is the one you have the most fun using (as long as your character survives to use it another day).
Level 4 sneak attack with hand crossbow and 18 dex: 3d6+4= 14 or 15 average
Level 1 Catapult: 3d8= 13 or 14 average
Level 4 Catapult: 6d8= 27 average
Level 19 sneak attack with hand crossbow and 20 dex: 11d6+5=48 or 49 average
As you can see, it doesn't really hold up in terms of damage though. Not for an Arcane Trickster who only ever gets as high as level 4 slots at least.
did you guys homebrew that booming blade does damage when they aren’t moving?
Booming blade does damage up front starting at level 5. More at higher levels. So does Green Flame Blade. Since rogues only get one attack, they are really good because they add that up front damage and can be combined with sneak attack. At 5th level currently, I rarely leave anything alive long enough to get that secondary damage from it moving. I've found my melee attacks kill most things we've encountered in one shot.
Damage is something like 1d8+1d8+3d6+4= 23 or 24 damage on average at 5th level. Doing that every round because i get advantage so easily is nice. 9-38 damage. More if they are foolish enough to move and take another 2-16 Thunder. Seems pretty good for the level.
I might be playing an arcane trickster soon and the DM has mentioned their initial disinterest in booming blade with sneak attacks, given the converse nature of both things. I got him to swing his vote my way though. I'm looking forward to seeing it in action.
Oh, how do you guys use illusion spells? They seem really great in potential, but i'm yet to actually play mine so i don't know how effective they are for this class.
Phantasmal force is great to use against a dumb npc. I usually say; "it sees a rival," or I say; "there is a bridge over the chasm". The limits are your cleverness and your imagination.
Silent Image is very useful too. I recently used it to create a floor at waist height. This had the effect of the illusory floor having holes in it where the invisible creatures were standing, allowing us to know which square to attack. It's one of those spells that is great for creative people.
Silent Image is very useful too. I recently used it to create a floor at waist height. This had the effect of the illusory floor having holes in it where the invisible creatures were standing, allowing us to know which square to attack. It's one of those spells that is great for creative people.
If things can pass through the image, why would there be holes in it where invisible creatures are standing?
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The Ready action lets you ready any action you can take, including Attack, but Extra Attack is on your turn.
-Jeremy Crawford
One spell that can be great for an Arcane Trickster is Shadow Blade. Sure, you don't add your modifier to damage, but you get advantage on attack rolls with the blade made in dim light or darkness AND the damage is all psychic damage. So if you Sneak Attack with it at 9th level (when you can learn the spell), that's 2d8+5d6 psychic damage.
Another minor plus for this is that Shadow Blade is an Illusion spell, so it doesn't take up one of your precious non-trickstery spells
You get your dex (or str if you prefer) mod to attack and damage with the shadow blade, it is effectively a normal melee weapon that does 2d8 psychic for its damage dice.
Don't you learn second level spells at 7th level?
Correct. You get Shadow Blade at level 7, and you can add dexterity or strength to the damage.
I've found that Minor Illusion + Mage Hand is a great way to open a door. You use minor illusion to create a hiding place for yourself 30ft away from the door, and then you use your invisible Mage Hand to open the door. If the enemies in the room have heard the combat going on nearby, it's not unreasonable for the DM to have them readying an action to attack whoever opens the door. It's very videogamey and unrealistic for enemies to be completely oblivious to combat going on less than 100ft away just because it's on the other side of a closed door. If they didn't come rushing out to help, they're probably planning to ambush whoever opens the door.
If you're using the Booming Blade cantrip, expect your DM to consider combat to be quite loud. Even without using that spell or other loud spells, expect combat to be pretty loud. Especially if your players are trying to communicate to each other during combat. Booming Blade is an awesome cantrip, but it can cause the DM to send waves of enemies at you, instead of you getting to come to them.
Another trick with minor illusion / silent image is making a replica of an opening. For instance you are exiting a cave but scout ahead and see a bunch of goblins ready to ambush you. So you create an illusion of the cave mouth itself. That way the goblins can’t think they are still looking at the cave mouth entrance but your party is sneaky slowly up behind it. Once your party member said touch it they auto-see through the illusion while the goblins are most likely unaware of anything other than the normal cave opening.
I'm currently playing an Arcane Trickster and my suggestion would be to avoid using one of your precious few cantrips on Firebolt or any of the ranged attack cantrips. I highly suggest Booming Blade, Minor Illusion, and Mage Hand to start off. The thing about ranged attack spells is that you can just use a Hand Crossbow and keep your sneak attack damage and be using your primary attribute of Dex, which is what you'll most likely be increasing over time. Booming blade is great because it works with your dex and your sneak attack, but otherwise, I suggest using cantrips, which you cannot change later, for things that will give you the greatest utility. Booming blade is the only attack cantrip you need and minor illusion is incredibly useful.
For first level spells, I took Find Familiar, Silent Image, Disguise Self and Charm Person. Really good spells, but I'm yet to find a use for Charm Person. I think it's great, but extremely situational and I'll probably temporarily give it up when I get access to 2nd level spells (I'm level 5). For find familiar, I use a Tressym. Owl is optimal, but Tressym's ability to see invisible things has saved us some pain. Any familiar that can be there to grant you that sneak attack is a solid choice. The Dodge action is their friend if they aren't an Owl. Barding to up their AC if you are allowed.
For second level spells, I don't have them yet, but I'm looking closely at Invisibility and Mirror Image. Shadow Blade is good too, as it works well with your rogue abilities and scales. It's concentration, so that's yet another point in Mirror image's favor over Blur. Mirror Image will help you keep Shadow Blade going, but remember that even though one is a bonus action, you cant cast both in one turn. This is when you start to wish you had Shield after all, despite Uncanny Dodge.
I agree with your comment about using one of your precious Cantrip slots on a ranged spell attack cantrip. It's such a waste when there are so many good options there instead.
Mage Hand is required, so you only get two choices for cantrips until you get a 3rd choice at level 10. It's best to take one melee attack cantrip and one utility cantrip with these two cantrip choices.
Message is a great cantrip if you're acting as the party scout. Control Flames is useful if you're trying to fight in the dark. These two cantrips have very specific uses, but these can be uses that are both important and frequent, despite being so specific. On the other hand, Minor Illusion is incredibly useful and can be used for such a wide variety of purposes. Prestidigitation is also a cantrip which can be used in such a huge range of situations.
Booming Blade is better than Green Flame Blade most of the time, but it's acceptable to take Green Flame Blade instead of Booming Blade (primarily if you want to stay somewhat sneaky in combat). If you're going to be at level 5+, it's pretty important to have taken either Booming Blade or Green Flame Blade. Without it, you'll have such a low amount of damage on the turns when you aren't able to get sneak attack.
A kenku(preferably) or variant human(with actor feat), disguise self(cannot easily discern you aren't the same person), silent image(kenku uses voice to create sounds and voices), definitely grab find familiar, maybe dip into warlock 2 for infinite disguise self's and other utility? Like devil's sight + extra spells.
I think I took fire bolt and friends as my cantrips. Which sucks since I barely use them and this was one of my first 5th edition characters. (My next was a hexblade and I took true strike... I didn't learn.)
But, I did get minor illusion from my tiefling variant and multiclassed into bard for predidgitation and vicious mockery.
I am mostly using my bow to deal damage so booming blade and green flame blade wouldn't help me much anyway.
For my non illusion/enchantment spell I took shield which is coming in pretty handy since I only have a 16 AC and sometimes uncanny dodge just doesn't cut it, however, absorb elements may be able to protect me better against things that shield and uncanny dodge cannot.
One spell I have yet to see in this thread that's surprisingly excellent for Tricksters is Catapult.
Catapult allows you to select one object weighing between one to five pounds anywhere within sixty feet, and cause it to rocket ninety feet in any direction you choose. You can 'shoot' people with it, forcing the first critter in the line of motion to make a Dex save or suffer 3d8 bludgeoning damage (some DMs will be willing to negotiate on this for items such as "Flask of acid", so keep that in mind!). Upcasting the spell gives you an extra five pounds of weight you can Catapult (so 10 pounds for a level 2, 15lbs for level 3, and so forth), as well as an extra 1d8 bludgeoning damage.
"Why is this weird girl yammering on about a spell that lets you improvise basic bludgeoning damage like a nerd instead of cool illusion spells?" you ask?
Catapult requires nothing but somatic components. No verbal, no material. Nothing but somatic.
Post up in a good hiding spot (or make one with Minor Illusion) and prepare your Poltergeist show as random items in wherever you are fly in directions you choose. You can spook superstitious things or frighten animals - or, if you target a log in a fireplace, you can start a fire without anyone else being the wiser as to your location. Get Magical Ambush at 9th level and you can impose disadvantage on any given critter's save vs. telekinetic bullhonkey, and again - no verbal components, no material components, no flash or spectacle.
One item within sixty feet of you flies at damaging velocity ninety feet in a straight line, and unless you give the game away some other way, your Trickster remains perfectly hidden and ready to do it again, or to take advantage of the confusion Ork McGork's face suddenly being covered in alchemist's fire causes to start with the crossbow bolts.
Catapult. It's better than you think it is for Tricksters.
Please do not contact or message me.
Also, I think Shadow Blade is very good, 2d8+dex, advantage if in darkness or dim light(perfect for rogues), if with advantage, sneak attack. Incredibly useful if your Dm allows you to stack advantages.
Multiclassing for vicious mockery for someone who has both firebolt and a bow is an unusual choice. I'd be hesitant to slow down my spell and sneak attack progression without a really good reason. In my opinion, you should have taken either of the ranged damage cantrips. Unless you hate using sneak attack for some reason, just use your bow.
I will say that Friends is an okay pick if you also take Disguise Self. In combination, it will leave them angry with someone else.
The only real use I've ever found for Prestidigitation is cleaning things really well, but I know people talk about how useful it is. I'm yet to see it.
I think Half-elf is a great race for the Arcane Trickster too. I find that talking is an important part of what most Tricksters get up to and you get 8 skills. I personally wouldn't multiclass into a warlock, but if you did, you could take beguiling influence and have 10 skills. Skills are kind of a big deal for rogues and a rogue with high intelligence, dexterity, and charisma can be really good at a lot of different things that aid in an Arcane Trickster lifestyle.
I never have issue getting advantage. Between a familiar, hiding, and teammates I'm good. Bonus action hide tends to work well in dim light or darkness to begin with. The extra 1d8 is fine, but loses it's appeal quickly if you have a magical weapon(which you usually have by 7th level). It's also concentration for a melee spell on a character with no proficiency in con saves, a relatively low AC and few spell slots. A +1 Rapier and a different spell choice will likely be the route I take. I would take Shadow Blade for a Crit Fisher maybe, but i'd make sure to have Mirror Image and Shield or some other additional defense prepared to keep the spell up. You will get hit.
Interesting. I'd worry about having enough things to use. I imagine there wont always be something present at your location, which means possibly carrying numerous various weights of objects to use as ammunition. While a hilarious idea and pretty decent damage, there are some issues even if you don't have any with finding or carrying ammunition. One is that the damage is roughly the same as just sneak attacking with a hand crossbow when you get the spell and it doesn't compare to sneak attack so well as you level. Another is that the weight and distance limit keeps you from doing so many fun things you might think of with it. I personally prefer a damage type more exotic than bludgeoning on an attack spell, since spells are good to resort to when traditional weapons don't work well. You are more likely to want to increase your dexterity than intelligence early on too, so a spell they may resist eating a spell slot in the attempt is fine, but not great with a little bit of a lower save for a while.The last thing is that it takes your precious spot for a non-enchantment, non-illusion spell (so many good choices). With damage that weak, I'm not sure if the hilarity is worthy it. You can get advantage on your hand crossbow attacks right out of the gate too. This is all purely optimization talk. It seems maybe good against low dex heavily armored opponents and have some fun utility though. In the end, the best spell is the one you have the most fun using (as long as your character survives to use it another day).
Level 4 sneak attack with hand crossbow and 18 dex: 3d6+4= 14 or 15 average
Level 1 Catapult: 3d8= 13 or 14 average
Level 4 Catapult: 6d8= 27 average
Level 19 sneak attack with hand crossbow and 20 dex: 11d6+5=48 or 49 average
As you can see, it doesn't really hold up in terms of damage though. Not for an Arcane Trickster who only ever gets as high as level 4 slots at least.
did you guys homebrew that booming blade does damage when they aren’t moving?
No homebrew. In my example, Booming Blade does upfront damage because he is above level 4.
"Not all those who wander are lost"
Booming blade does damage up front starting at level 5. More at higher levels. So does Green Flame Blade. Since rogues only get one attack, they are really good because they add that up front damage and can be combined with sneak attack. At 5th level currently, I rarely leave anything alive long enough to get that secondary damage from it moving. I've found my melee attacks kill most things we've encountered in one shot.
Damage is something like 1d8+1d8+3d6+4= 23 or 24 damage on average at 5th level. Doing that every round because i get advantage so easily is nice. 9-38 damage. More if they are foolish enough to move and take another 2-16 Thunder. Seems pretty good for the level.
I might be playing an arcane trickster soon and the DM has mentioned their initial disinterest in booming blade with sneak attacks, given the converse nature of both things. I got him to swing his vote my way though. I'm looking forward to seeing it in action.
Oh, how do you guys use illusion spells? They seem really great in potential, but i'm yet to actually play mine so i don't know how effective they are for this class.
Phantasmal force is great to use against a dumb npc. I usually say; "it sees a rival," or I say; "there is a bridge over the chasm". The limits are your cleverness and your imagination.
Silent Image is very useful too. I recently used it to create a floor at waist height. This had the effect of the illusory floor having holes in it where the invisible creatures were standing, allowing us to know which square to attack. It's one of those spells that is great for creative people.
If things can pass through the image, why would there be holes in it where invisible creatures are standing?