Hiya,

When the Artificer was in UA, I was working on an Iron Man subclass. Now that Eberron is out, I need to revise my homebrew.

Since the Artillerist and Battle Smith both cover range and melee attacks, I want to focus more on being able to tank and defend the party, with subclass features at least.

The issue I'm having is I'm just aping fighter stuff.

So for 3rd level, I have you get your suit of armor, resistance to psychic or poison (can't decide, but I wanted the armor to provide some form of insulation), and it counts as your arcane focus. I thought about giving them access to Heavy Armor, but I don't know if that's too much.

For 5th level, I wanted to mimic either Sentinel (feat), or Protection (fighting style) a number of times equal to your Int Mod (min 1).

After that I'm at a loss for 9th and 15th level. 

If anyone has any ideas, I'm open to listening to them.

Things I've thought of:

• Selecting an element that the armor absorbs, then unleashing the energy for something?
• Selecting an element and spending your Reaction to give a party member resistance to that element?
• Damage Reduction?
• Ignoring a critical attack on yourself? I don't know how often something like this would happen, so maybe combo this with another feature. I also don't know if this is so rare that it should always happen, or if it has limited uses. 

A bit off topic and I’ll try circle around for some additional ideas later but I always thought that Battlesmith could have posted with an Armor instead of a pet, So is a fertile ground for Homebrew.

Instead of steel defender you create a suit of armor that gives you access to BA dealing d8+Prof and a RA that imposes DisAdvantage. Your standard attack is still Martial weapons and Extra Attack make sense as the suit enhances you. Then both Arcane jolt and the RA damage also make sense as lightning powers from the armor.

Variant feature anyone?

So for the third level, my mind goes to either granted straight up resistance to a changeable damage type that you can set at the end of a long rest, and as they take more levels in this class they can add one or two more resistances as well.

Another would be to go with the Heavy Armor master of things, and just straight up subtract from damage you receive.

it sounds like maybe the function you want to serve is tank, so maybe something like targeting system, so that you can now make attacks of opportunity without expending your reaction.

If I was home brewing this I’d probably give straight Heavy armor and maybe a BA Attack option. However since I may be influenced by Ironman, I’d let this character be a strong Cantrip user rather than going weapons. Maybe granting Eldritch Blast or roll the dead with added damage boost at 5th level. Then some flight or support skills in levels 9+15.

Flying heavily armored but not high health Long range cantrip user would be interesting and keep it distinct from standard Heavy armor melees like Fighter and Paladin.

Quote from Zoken44 >>

So for the third level, my mind goes to either granted straight up resistance to a changeable damage type that you can set at the end of a long rest, and as they take more levels in this class they can add one or two more resistances as well.

Another would be to go with the Heavy Armor master of things, and just straight up subtract from damage you receive.

it sounds like maybe the function you want to serve is tank, so maybe something like targeting system, so that you can now make attacks of opportunity without expending your reaction.

I’d recommend being careful copying Infusions or feats for subclass features but am actually pretty interested in the multiple reaction suggestion for 5th level. It is like Extra Attack but less in your control.

Well, my thought was simply "Starting at 5th level, if an enemy leaves your melee range without disengaging you may take an attack of opportunity without having to use your reaction."  Maybe put a hard limit of number of times per day on that to your intelligence modifier.

Also, as for the third level armor feature how about this "While wearing this armor, you may reduce Bludgeoning, Piercing, and Slashing damage by a number equal to your intelligence modifier"

I want to avoid any "flying DPS" because I don't want to step on the Artillerist's toes (plus I think flying is a little op).

I could do something similar to 3.5's Combat Reflexes, which gave you multiple Opportunity Attacks,  but I don't know how to word it without changing how reactions work. This would also be way better than Sentinel, but I don't know if that's a good or bad thing.

I thought maybe as a 9th level feature, I was thinking something like giving yourself immunity to an element and resistance to allies (1 per Int Mod) for like ten minutes once per day. Something useful for that one, important fight each day.

Quote from Zoken44>>

Also, as for the third level armor feature how about this "While wearing this armor, you may reduce Bludgeoning, Piercing, and Slashing damage by a number equal to your intelligence modifier"

That gets you -3, maybe -4 each attack that hits? Is that enough, or is that going to matter nil late game?

How about this for a 5th level ability:

You spend a bonus action to "hunker down" or something. While in this state, you can't be moved (or you have Advantage on rolls to be moved). In addition, anyone passing by you takes XdY damage (that jumps to 2XdY at 9th or 15th). That leaves your Reaction free and as long as this extra damage is less than your opportunity attack it should be good. 

Also instead of a flat damage reduction, what if you spent a spell slot and got Xd6 (X=spell slot level) in DR?

I like the Spending a spell slot for variable DR option, but maybe add in a once per day free one, like the arcane cannon.

As for Hunker down....

"Hunker Down: once per day you may spend a bonus action to increase the sturdyiness of your armor.  While in this state, you cannot be moved by force, your movement speed is halved, and you roll 2d6.  As long as you are in this state, the result of the 2d6 is subtracted from all incoming bludgeoning, piercing, and slashing damage.  You may do this once per long rest at no further cost, however you can spend a spell slot of 1st level or higher to enter this state.  If you spend a spell slot of 2nd level or higher, and 1d6 for each level of the spell slot above first."

"Automated Defenses: you have a minor arcane turret mounted on your armor. It is activated when you use your Hunker Down feature.  If a creature were to move out of your melee attack range, or otherwise provoke an attack of opportunity, the turret will make a spell attack against them using your spell attack modifier dealing 1d4 + your intelligence modifier of force damage to them on a hit.  this does not use your reaction.  If you do use your reaction to take an attack of opportunity, the turret recognizes this, and does not attack them."

I created this archetype bach when the Artificer (UA) 1st went live, then upgraded it. It's based on a combination or the Artillerist and Battle Smith.

Requires a suit of non-magical armor you are Proficient with ( I am currently using half plate)
- this replaces Turrent (Arcane Cannon now) and Iron (Steel) Defender
- currently I use Battle Smith as a template, replacing the Steel Defender

3rd level:
a) The armor becomes magical. You reduce the amount of damage you take from an attack by 3.
b) Chose one of the following:
    . Defensive - add your Proficiency Bonus to your Armor's AC
    . Offensive - You can fire a blast of energy, chosen at the time the armor is activated (Acid, cold, fire, lighting, or thunder). This blast is used as an Attack action and works with Extra attack. It does 2d6 of the selected damage type. Range: 60/150
    . Support - Creates a defensive field that grants each chosen creature in a 10-foot radius temporary hit points (1d8 (5) +INT mod)

9th level
Based on chosen Armor mode:
. Defensive - You gain Resistance to a selected damage type (Acid, cold, fire, force, lightning, necrotic, radiant, or thunder)
. Offensive - add Necrotic, Radiant, and Force to your available damage types
. Support - Choose one of the following movement speeds to your armor (fly, swim, climb, burrow). You gain a movement speed in your chosen type equal to your walking speed.

15th level
Based on chosen armor mode:
. Defensive - As Fire Shield except chose from (Acid, cold, fire, force, lightning, necrotic, radiant, or thunder) damage types.
. Offensive - Increase the amount of damage done by your blasts of energy to 4d6.
. Support - You gain the ability to use Misty Step as a Bonus Action once per round. In addition, you can take one creature with you (of your size). If you do so, you cannot use this feature again until you have finished a short rest.

This is my current implementation. The 15th level features have nit yet been tests since the group testign this have only recently reached 9th level.

Some very rough ideas but here is my take on an armored sub class.

3rd using a combination or magic and technology you animate an existing suit of armor that you are proficient with. This armor can be non magical, infused or magical. You may don or remove the armor as an action. While wearing the armor you receive D6+INT modifier temp HP every round (min 1, non cumulative) as the armors systems shift to intercept attacks. If you become Incapacitated or are reduced to 0 HP while wearing the armor it automatically stabilizes you and takes the Dodge action. An ally with the command word may also use a bonus action to command the suit to take the Dash action. Your Animated Armor may be used as your spell focus item. This armor does not require attunement unless the enchanted armor requires it.

5th Extra Attack and Heavy Armor proficiency

9th Advanced Systems. Your armor gains either the Auto Injector mod, Enhanced Motive Systems or Augmented Enchantments.

Auto Injector - Your armor holds up to INT mod potions. These are considered readied and may be used as a bonus action. Healing potions may be set to use if you fall below 0 HP.

Enhanced Motive Systems - your armor grants you the ability to use certain bonus actions based on the class. Light grants the Dash action, Medium the Dodge action and Heavy the Disengage action.

Augmented Enchantments - You may add a second infusion to your armor or add one to existing Magical armor. You may add the following infusions: Enhanced Arcane Focus, Enhanced Defense, Repulsion Shield, Resistant Armor, Replicate Magic Item (Arm Blade, Wand Sheath, Arcane Propulsion Arm [weapon feature only]). Animated Armor with this enhancement requires Attunement, but only counts as a single item. The bonus to AC form magic armor and infusions do not stack. In the case of Wand Sheath you must still attune to the wand separately, which is not lost when removed

15th Temporary HP increase to 2D6+INT mod. While wearing your armor you may cast the Sword Burst cantrip as a bonus action. You may do so a number of times equal to your INT mod (min 1) per day, regaining all uses on a long rest.

Thanks for the ideas, folks. That helped me out a bunch. So a little more explanation for the subclass: I'm making the subclass for a gnome artificer who worked on the first prototype for what would become Warforged. The idea I has was one group was working on the shell when another group developed the "guts and soul" for the Warforged (RIP Archivist).

Here's what I got so far.

3rd Level:

• Create Mobile Construct: Whenever you finish a long, or short rest, you build a construct that you can sit inside and pilot. You can enter or exit the Construct with a bonus action. While inside, the construct counts as your Arcane Focus and you are considered a medium creature: increase your height by 4 feet and your weight by 200 pounds. The construct shares your AC and gains an additional +1 bonus to Armor Class. The Construct falls to pieces if you are reduced to 0 HP or less while inside it, are targeted by effects that dispel magic, or if you dismiss it with a bonus action. When outside of the Construct, it is considered a medium sized object with 1 HP per artificer level and AC 15. While an object, the Construct has no Move rate and will fall to pieces if reduced to 0 HP or less. It can be moved by an outside force, but otherwise just stands in its space.
• Ablative Armor: While building your construct, you may also spend a spell slot to fortify it. Gain Temp HP equal to 4 per level of the spent spell slot. If you have any Temp HP left when you dismiss the construct, you create a small explosion. Each creature other than you in a 20-foot-radius sphere centered on your location must make a Dex Save. Each target takes 1d8 bludgeoning damage on a failed save, or half as much damage on a successful one. This damage increases to 2d8 at 12th level.

5th Level:

• Elemental Runes: Whenever you finish a long or short rest, you can mark your construct with special elemental runes. You have resistance to this element until you use this feature again. In addition to resistance, whenever a creature moves out of your melee reach, you can zap them with a bolt of elemental energy. Make a ranged spell attack. On a hit you deal (elemental type) damage equal to 1d4 + your Int Mod. This the damage increases to 2d4 + your Int Mod at 15th level. You can do this a number of times equal to your Int Mod (min 1) and regain all uses after a long or short rest. This does not use your Reaction, but you cannot target a creature with this feature and an opportunity attack in the same round.

9th Level:

• Elemental Ward: As a bonus action, you can empower your elemental runes for a short while. For the next ten minutes, you have immunity to the chosen element type and grant resistance to up to four other creatures. You regain this feature after you finish a long rest.

15th Level:

• Adamantine Scales: Gain resistance vs non-magical attacks. You may also ignore a critical hit once per long, or short rest.

(edits are for simplicity, either removing features or simplifying them for less book work)

Hmm, sorry for necro.

but it is incredible to see how this idea started and what WOTC ended actually making. It’s fascinating as there are a lot of similarities.
: )