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DnD 5e - The Armorer Artificer Handbook

Disclaimer

RPGBOT uses the color coding scheme which has become common among Pathfinder build handbooks, which is simple to understand and easy to read at a glance.

  • Red: Bad, useless options, or options which are extremely situational.
  • Orange: OK options, or useful options that only apply in rare circumstances.
  • Green: Good options.
  • Blue: Fantastic options, often essential to the function of your character.

I will not include 3rd-party content, including content from DMs Guild, even if it is my own, because I can't assume that your game will allow 3rd-party content or homebrew. I also won't cover Unearthed Arcana content because it's not finalized, and I can't guarantee that it will be available to you in your games.

The advice offered below is based on the current State of the Character Optimization Meta as of when the article was last updated. Keep in mind that the state of the meta periodically changes as new source materials are released and this article will be updating accordingly as time allows.

RPGBOT is unofficial Fan Content permitted under the Fan Content Policy. Not approved/endorsed by Wizards. Portions of the materials used are property of Wizards of the Coast. ©Wizards of the Coast LLC.

Introduction

Armorer is my single favorite subclass in the game from an optimization standpoint. While your damage will never be stellar, it can certainly be good enough and you make up for it by either being an objectively phenomenal Defender or a strong contender for best skill character and Scout in the game.

This guide is specifically for the Armorer Artificer, and omits sections of typical class handbooks when those sections aren't meaningfully different from other members of the class. For more information on the Artificer, see the Artificer Handbook. I also strongly recommend reading the Artificer Spell Lists Breakdown and Artificer Infusions Breakdown.

Armorer Subclass Features

  • Armorer Spells None of these spells are bad and even the least immediately useful one, Passwall, is still situationally helpful. The only problem is that, as an artificer, you can't actually cast all that many spells and the default attacks with either version of the armor are so good that there's rarely a point to using the damage spells.
    • 1st-level Spells Magic Missile ironically misses the mark here. Spending one of your limited spells on 3d4+3 damage when an attack with your armor is either going to do 2d6+int or d8+int and taunt feels incredibly wasted. This only becomes more evident when you reach level 5 and get extra attack. Thunderwave, on the other hand, is great. While it does target con saves and is therefore more likely to be resisted by monsters, it's good damage and if they fail can help you get a moment to breathe.
    • 2nd-level Spells Mirror image is one of the best defensive spells out there, and having access to it as someone in heavy armor is exciting. Shatter is underwhelming AOE damage, but the Armorer has few other options to handle crowds.
    • 3rd-level Spells Just wow. You get one of the best AOE control spells and then also the required competitor to Fireball. Admittedly using Lightning Bolt is harder because it's a line, but that also makes it much easier to aim around your friends.
    • 4th-level Spells Another amazing level. Greater invisibility is a staple spell and the uses for it are only limited by your imagination. Fire Shield is great for giving yourself another resistance if you aren't already resistant to both fire and cold, although the rider effect is a bit wasted as not much should be hitting you all that often at this level due to either your high AC or being removed from melee.
    • 5th-level Spells Passwall at this level is generally only useful if no one else has any spell slots left for teleport. Wall of Force, on the other hand, is another incredible Swiss Army knife of a spell. Section off a fight. Trap someone in a sphere and walk away. Options abound.
  • Tools of the Trade Picking up free armor proficiencies is always a good thing. Heavy armor in particular is required to make one version of the class function and is a lovely side of gravy for the other. The free smith's tools proficiency is a nice piece of flavor but is really just there to make the next part possible.
  • Arcane Armor Robert Downey Jr has nothing on you. You now wear your focus, use full plate with strength 8 and no drawbacks, and can take it off as an action to sleep. Everything about this is mouthwatering.
  • Armor Model Oh no wait it gets better. What would you like your subsubclass to be? Guardian gets the only unlimited “tanking” mechanic in the game and the capacity to self-generate temp hp to help offset the d8 hit die, whie Infiltrator means that you can take that full plate and walk around in it, quiet as a church mouse. A very fast church mouse. That shoots lightning. It is worth noting that you can change which model you have as part of a short or long rest, but if you're optimizing, you're still going to have a primary role that you expect to be in.
  • Extra attack Very boring, but still very good
  • Armor Modifications One of the hardest parts of playing artificer is figuring out where to spend your infusions. Because they can be given to friends, there can be a legitimate expectation that you don't keep all of them yourself, particularly if you're in a low-magic setting where magic items are harder to come by. This gives you two free ones that can only apply to you, thus helping to alleviate part of the strain. Also, creating extra slots on you means you can have some of the best options while continuing to wear your suit.
  • Perfected Armor The guardian version of this is good but competes for your reaction with the other amazing Artificer ability Flash of Genius and, considering that your job is protecting people, only using your reaction to pull something and punch it when you could be giving them a massive bonus on, for instance, a save vs finger of death is inevitably going to lead to some moment where you tear your hair out because you already used your reaction. The Infiltrator version is phenomenal. If your first attack hits the benefits apply to the second attack so you're always going to want to save your extra d6 for the second roll as the advantage makes it more likely to crit and multiply the bonus die.

Ability Scores

Like any other caster class, your primary stat will be that which controls your spells. Max Int first, and your second highest should be dictated by what your primary role is going to be.

Str: You can't afford to have high ability scores in four abilities, and Strength simply isn't useful enough.

De x: Guardian primaries won't need any. Infiltrator primaries will take this after int to help with stealth and sleight of hand, as well as filling out the breastplate cap.

Co n: Guardian primaries will bump this after int. Infiltrator primaries still want some but having proficiency on con saves helps enormously with maintaining concentration and you shouldn't need all the hit points your tank cousin does.

Int: You are powered by Int.

Wis: Dump.

Cha: Dump

Point Buy Standard Array
Str: 8Str: 8
Dex: 14 (15)Dex: 14 (13)
Con: 15 (14)Con: 13 (14)
Int: 15Int: 15
Wis: 10Wis: 12
Cha: 8Cha: 10

Races

Ability scores are crucial for the Armor Artificer, but also easy to achieve. Look for some combination of Intelligence and either Dexterity and Constitution in most cases. Beyond that, innate spellcasting or things that improve your durability for Guardian primaries or your proficiency/skills for Infiltrator primaries are great options.

The list of races and subraces below is intentionally reduced to those options which I think make an effective Armorer Artificer or which offer traits which are illustrative of what you should look for in other races, and it does not address the Customizing Your Origin optional rules. These are by no means the only viable options (especially with the optional rules in place), and I encourage you to explore other options not listed below. For full race coverage (including discussion of options which work well for the Armorer), please see my full Artificer Handook's Races section, which includes the full range of available races.

Dwarf: While not allowed at every table, I will plug the utility of a Mountain dwarf having a staggering 7 racial proficiencies which can all be turned into tool proficiencies if you're customizing your origin as per the optional rules. This makes the Fabricate spell you will learn later on very powerful as you can craft really anything you like with the right raw materials.

Elf PHB Dexterity is helpful for Infiltrator mains, and Perception is always nice. Guardian mains should likely choose races with Constitution instead.

  • High PHB : The stats are good and an additional cantrip is excellent since the Artificer starts with so few, but the weapon proficiencies are largely useless. If you're using a weapon other than your armor something's gone horribly wrong.

Genasi: Only one is worth looking at.

  • Fire Genasi EEPC : Good stats for a Guardian primary, but there are still better options. The innate spellcasting is Constitution-based, so it won't keep up with your class spellcasting.

Gnome PHB : Intelligence is the biggest priority, and gnomes have plenty of it.

  • Deep Gnome PHB : Deep gnomes have the perfect spread for Infiltrators and some amazing side benefits.
  • FForest Gnome PHB : Stats are still great for Infiltrator mains, but you can get better perks.
  • Rock Gnome PHB : Strong contender for the best race for Guardian mains outside of Customizing your Origin. Great stats and a very thematic set of extras.

Hobgoblins VGtM : A reasonable choice for Guardian primaries thanks to their spread and letting you get a bonus to a crucial attack to apply your debuff.

Human PHB: Versatile and fantastic at everything.

  • Variant You still get a crucial bonus to your Intelligence, and you can get an awesome feat at level 1.

Tiefling, Feral SCAG : The stats are decent for Infiltrator mains and fire resistance is always appreciated. Winged won't work for Guardian primaries since you'll be wearing heavy armor, but it's great of Iniltrator primaries. The innate spellcasting being charisma-based means that it's much less attractive than they could be.

Lineages

All lineages are inherently strong because they let you choose your ability spread regardless of other optional rules being used. If you take a lineage on top of an existing race, you can keep many of the benefits of the original race such as proficiencies and languages.

  • Dhampir VRtR : A fantastic selection for Guardian primaries as you'll be focusing Con secondary anyway and Spider Climb is nearly as good as flight for many purposes.
  • Hexblood VRtR : Giving your Eerie Token to your Homunculus is a great way to make it an even better familiar, and Hex Magic is decently helpful.
  • Reborn VRtR : While the benefits aren't flashy, they're really good. You're very durable thanks to Deathless Nature and Knowledge from a Past Life will help you succeed on those critical lockpicking/door-inspection checks.

Setting-specific races are addressed below. Not every setting allows every race, and, while most races presented in the core rules and in content for the Forgotten Realms can be used in other settings, races specific to settings like Ravnica aren't typically allowed in other settings. Talk to your DM about what races are allowed in your game.

Races of Eberron

Warforged ERLW The flexible ability increase goes into Intelligence, and the Warforged's other traits will make you a quite durable Guardian primary. As an added bonus, you can be the watch rotation at night all by yourself for optimal party protection.

Dragonmarks

While the design intent for Dragonmarks was that they would offer some innate spellcasting for everyone, every dragonmark includes an expanded spell list which is arguably a more significant benefit than most of the provided racial traits. Because the expanded spell options are such an important part of the dragonmarks, if you're not playing a spellcaster you're giving up a huge part of your racial traits, which makes it exceptionally difficult to justify playing a dragonmark character who can't cast spells.

Dragonmarks are uniquely helpful for the Artificer. Any amount of extra spellcasting can significantly improve your capabilities since your spell slots are so limited.

Dragonmarked Dwarf ERLW Dragonmark traits replace your subrace.

  • Mark of Warding Ok spread and only passable free spells, but the additional spell list is pretty good and adding a d4 to checks Infiltrator primaries plan on making fairly often is great.

Dragonmarked Elf ERLW Dragonmark traits replace your subrace.

  • Mark of Shadow Tempting spells for an Infiltrator primary, but the bad spread means we should look elsewhere.

Dragonmarked Gnome ERLW Dragonmark traits replace your subrace.

  • Mark of Scribing Better than Mark of Shadow because at least you still get +2 int, but still not a great choice.

Dragonmarked Human ERLW Dragonmark traits replace ALL of your racial traits.

  • Mark of Making Perfect ability increases and some wonderfully thematic extras. While there's certainly some overlap in spells, mending for free is fantastic and worth not expanding your options by all that much.
  • Mark of Passage A good enough spread for Infiltrator primaries and a good selection of new spells.
  • Mark of Sentinel Guardian primaries will enjoy the stat spread and many of the additional benefits.

Races of Ravnica

Simic Hybrid GGTR : The constitution increase is helpful for Guardian primaries. Animal Enhancement offers several excellent options as you gain levels, and saves you the trouble of getting those effects from your limited number of spell slots.

Vedalken GGTR : Incredibly satisfying for Infiltrator primaries. Advantage on Wisdom saves helps protect your weakest common save and Tireless Precision is the best way to take your already incredible thieves tools checks and drive them through the roof.

Feats

My Artificer Handbook details advice for artificer feats in general, but a selection of feats which many Armorers enjoy are presented below.

  • Fey Touched Everyone likes teleportation and getting access to it and some for free is very helpful. Plus grabbing an extra 1st level spell is a great way to round out whatever you may be missing.
  • Mobile: A reasonable choice for Guardian primaries after you’ve capped int. This would help you apply your gauntlet debuff to multiple enemies in one turn or to Booming Blade someone before walking away, but since your AC is going to be astronomical you don’t so much mind the attack of opportunity you take to wall out of reach and if you’re taking the dash action you’re not protecting your allies. Mobile is also somewhat redundant with Boots of the Winding Path because you can use them to perform similar hit-and-run tactics, though Boots of the Winding Path eat your Bonus Action which should typically be reserved for your homunculus.
  • Sentinel Guardian primaries will enjoy the benefits of this feat in terms of making sure foes stay near them.
  • Shadow Touched Invisibility isn't as good as Misty Step but it's still very good and a lovely stop gap until you get Greater at high levels.
  • Skill Expert A fantastic choice for Infiltrator primaries, use it to go from no stealth proficiency to expertise immediately.
  • Skulker A passable choice for infiltrator primaries once you've maxed Int, particularly if you aren't taking a homunculus to help with perception checks.
  • Telekinetic Wow, what a good feat. Adding range to Mage Hand is one of the coolest things I've seen on a feat, and the amazing bonus action means that you functionally have a high chance of bonus action disengage against single targets, and that's just one of the uses for it. You can also Booming Blade your target and then push it away from you so it has to take the damage if it even wants to strike back.
  • Telepathic If you really need to be silent, this can be helpful. But all the limitations on this telepathy make it underwhelming when compared to the telekinesis listed right above it.
  • Warcaster Less useful than on most casters, but still very good for Guardian primaries wanting to Booming Blade anything that tries to walk past them.

Weapons

The only reason you need a weapon is to last you until you can wear armor, and then perhaps a melee weapon if you're an Infiltrator primary and not confident enough in your AC to walk away from things before you lightning them. Guardian primaries should be using cantrips for ranged attacks. Walk out at level 1 with whatever default weapons your background etc give you and mostly survive on cantrips until you're level 3.

Armor

  • Chain Shirt Your starting armor as an Infiltrator primary
  • Scale Mail Your starting armor as a guardian primary. Comes free with the class.
  • Breastplate Your permanent armor as an Infiltrator primary. Half-plate provides more AC, but it also imposes Disadvantage on Dexterity (Stealth) checks, which negates a major advantage from Infiltrator armor.
  • Full Plate Your permanent armor as a Guardian Primary.
  • Shield Always have a shield. You will either need one or no hands to use your suit weapon and casting is done via the focus you're wearing (remember that the Artificer can use any one of their Infusions as a focus).

Armorer Artificer Spellcasting

There's nothing really substantially different for Armorer Artificers. The same spells are still good for all the same reasons.

Armorer Artificer Infusions

Guardian primaries will want more defensive infusions while Infiltrator primaries will likely focus more on infusions that replicate magic items, although there's some that are always good.

  • Homunculus Homunculus is great for both flavors of armorer, and the absolute first thing you should pick as an Infiltrator primary. They have expertise in perception, which means that you can just use your action to aid their perception whenever you need to use your eyes for something instead of investigating with your tools. Plus they're one of the few ways of getting bonus action attacks, and it's force damage to boot. If I had a color past blue I'd use it for this.
  • Replicate Magic Item (Goggles of Night) Either needed for Darkvision if your origin doesn't provide it or adds more range if it does. Strictly a requirement for Infiltrator primaries and still a good idea for Guardian primaries.
  • Replicate Magic Item (Rope of Climbing) If you can't fly or spider climb, this is the next best thing.
  • Replicate Magic Item (Gloves of Thievery) If you're an Infiltrator primary and you expect to be anywhere near a lock, this is a nice bonus. By the time you can get it though you'll be getting expertise picking locks so it's a little overkill.
  • Replicate Magic Item (Winged Boots) Can't fly yet? Problem solved.
  • Replicate Magic Item (Cloak of Protection) One of the most boring mathematically fantastic items in existence.
  • Replicate Magic Item (Bag of Holding) You're not strong so, if there's no one else strong around to carry all your loot, this is a good way to haul it.

Example Build - Vedalken Artificer

Twenty years learning to make, twenty years learning to hide, and twenty years learning to find. Now I'm ready to begin my search for new knowledge, confident that I will find it behind any lock or guard, no matter what nook or cranny it's found to hide.

Abilities

We will assume the point buy abilities suggested above. Customizing our origin lets us shift that point of Wisdom to Dexterity for the final totals below.

Base Increased
Str 8 8
Dex 15 16
Con 14 14
Int 15 17
Wis 10 10
Cha 8 8

Race

Vedalken. Take Thieves' tools and Stealth For Tireless Precision.

Skills and Tools

Take Arcana, Medicine, and whatever tool proficiencies you like. You'll get smiths' for free soon and if you want to optimize for Fabricate I'd suggest woodworker's tools and Leatherworker's tools so you can fabricate armor later on, as well as whatever you want out of the incredibly abundant wood present in many settings.

Background

Take Cloistered Scholar for History and either Nature or Religion depending on what flavor of divine caster your party has.

Feats

We'll start at 17 Intelligence, so the level 4 feat can be a half-feat like Telekinesis or Skill Expert, then level 8 gets us to 20 and we can start branching out.

Levels

Level Feat(s) and Features Notes and Tactics
1
  • Magical Tinkering
  • Spellcasting
  • Spells Prepared:
    • Detect Magic
    • Cure Wounds
    • Tasha's Caustic Brew
  • Cantrips:
    • Firebolt Mending

For your starting equipment, take the money instead and buy a chain shirt and a shield. The only weapon you could use is a dagger and that will do less average damage than firebolt. Just keep your thieves' tools in one hand and your shield in the other. Feel free to draw the dagger if something closes to melee and you don't want to walk away.

Take detect magic because it can be ritual cast and you want to know what sweet loot you may have found under that false bottom in the chest or behind that locked door. Tasha's caustic brew will train you for how to find lines of enemies for when you get lightning bolt later. Plus it's another damage type.

At this level, you've got two spell slots so each one better be incredibly impactful. If your party is light on healing, saving cure Wounds for when someone drops unconscious is how many groups survive low levels. If you can afford to be a little more extravagant, try to line up 3 or more enemies for a Tasha's Caustic Brew, particularly if you know you're going to rest soon.

A keen observer will notice that we have not picked up proficiency in Investigation or Sleight of Hand. We never will, because a creative player will be able to use their thieves' tools for nearly all checks that matter for either of those skills and will get their Tireless pursuit bonus (and eventually expertise) that way. Think about the components and how you would use them to check for secret doors, hidden compartments, pressure plates. Maybe it's shims prodded around the edges of stones, mirrors getting you a better view of the insides or tops of things, etc. This is critical to the build.

2
  • Infusions:
    • Homunculus
    • Magic Item (Goggles of Night)
    • Enhanced Weapon
    • Magic Item (Bag of Holding)
  • New Spell Prepared:
    • Identify

Homunculus is a godsend. You now have a permanent partner to give you the Help action for Investigation checks and who can use Perception for you while you use the Help action to give them advantage. Goggles of Night means that you have the same Darkvision as your homunculus so you can now Help them see while stealthing around in the dark. Your help will cancel the Disadvantage from darkness and leave them rolling straight with Expertise. It will also help you spend a Bonus Action every round you're not doing something else with it. 1d4+proficiency force damage isn't much, but it's better than nothing.

Note that your homunculus can deliver touch spells for you, so a turn might look like “I ready an action to cast Cure Wounds when my homunculus is touching [target]” Then command it to fly there (possibly including dash) then use your reaction to cast then it uses its reaction to channel the spell for you”

You still don't have extra spell slots so let's take another ritual. Now you can discover the properties of all that sweet magical loot you found.

3
  • The Right Tool for the Job
  • Tools of the Trade
  • Armorer Spells
  • Arcane Armor
  • Armor Model
  • Retrain Cantrips:
    • Fire Bolt -> Guidance
Level 3 is every gift-giving holiday rolled into one. We technically have no decision points at this level but we're becoming the party's rogue-equivalent (also wizard and backup healer) so we're going to be making our chain shirt (unless you've been able to acquire a breastplate by now, then do that) into Infiltrator armor. 1d6+3 actually is a better average than Firebolt's 1d10 (avg. of 6.5 vs. 5.5) so we switch to the gem embedded in our chest which magically shoots lightning without requiring us to hold anything.Guidance is probably the mechanically best cantrip outside of combat, and we immediately start using it to make ourselves better at every skilled action we take when we're not pressed for time.You now have Advantage on all stealth rolls and 2d4 on top. We're getting there.
4
  • Feat (Skill Expert)
  • New Spells Prepared:
    • Alarm
    • Anything
Alarm is the final first level ritual you're going to use until you get better slots soon. The last choice doesn't matter so much for this level.For Skill Expert we choose +1 Int, gain proficiency in whichever of Nature or Religion you didn't choose at level 1, and gain expertise in Stealth. Your Stealth bonus now progresses faster than nearly anything, with Advantage, and an extra 2d4. Closer, but we can do better later.
5
  • Extra Attack 2nd-level spell slots
Chest lightning gets a huge upgrade. Remember that the extra d6 only applies once per attack, but it can apply to either attack and you don't have to choose before you roll. As long as either attack hits, that's 2d6+4, equaling a great sword. Drop the 4th-level prepared spells immediately for See Invisibility and Heat Metal. It's absurdly powerful against enemies with metal equipment and doesn't allow a save, even targeting worn or carried items.
6
  • Tool Expertise
  • New Infusions Known
    • Magic Item (Gloves of Thievery)
    • Spell Refueling Ring
  • New Spell Prepared
Expertise on all your lock-picking and door/floor/dinosaur investigation. You're generally going to want to infuse the ring but, if you know the day may involve lock-picking, put on the gloves and go to town. As far as spells go you really have all the tools you need at this point and can choose whatever seems to fit the day. Lesser Restoration, Invisibility and Darkvision are all decent options, particularly if you want to stop infusing your Goggles of Night and trade them for a spell slot.
7
  • Flash of Genius
Wow, what an incredible ability. Since it isn't specific about the type of saving throw, it can be applied to death saving throws if need be, but you're better off using it to prevent people dying in the first place. Or if you're having a social encounter kind of day, just throw a +4 onto someone's Persuasion.
8
  • Stat increase Int 18 -> 20
One of the few dead levels, but maxing Int has to happen and now's the time.
9
  • Armor Modifications
  • 3rd-level spell slots
  • New Spells Prepared:
    • Protection from Energy
    • Dispel Magic
You should now be running Enhanced Weapon on yourself at all times, and also looking at level 10 with longing.
10
  • Magic Item Adept
  • New Infusions:
    • Magic Item (Winged Boots) Helm of Awareness
  • Retrain Infusion:
    • Magic Item (Goggles of Night) -> Resistant Armor
  • New Cantrip:
    • Firebolt/Ray of Frost
Let's take full advantage of our new things. You can infuse all 4 pieces of your armor now (Helm of awareness, winged boots, enhanced weapon, and Resistant armor). Our other new feature gives us the 4th attunement slot to keep wearing our spell ring, once again trading out for gloves on a given day as needed. We would like a second damage type back in case something is resistant or immune to lightning which we'll be encountering more at higher levels so we bring back Firebolt, unless your campaign expects fire damage to also be ineffective. In that case, Ray of Frost will do just fine.
11
  • Spell-Storing Item
Does your primary Defender use Shield Master? Give them 10 hours of enhance ability per day.Party short on healing? 10 extra Cure Wounds. Going spelunking? Pass the Darkvision wand. Give someone an orb of Spider Climb. There are many good options here, and you can choose again every day.
12
  • Feat: Fey Touched
Take a +1 to Wisdom which we'll continue increasing later and pick up Hunter's Mark for your free Divination spell. 1-2 3rd level slots will make it last all day. Hunter's Mark is a fire-and-forget spell which adds a good chunk to our damage. It's a bonus action to cast or reapply and the wording doesn't require you to transfer it immediately on the target's death unlike some other effects, so you can just keep concentrating on it between fights and reapply as needed. You're proficient in Con saves and have a decent score to boot so you shouldn't have much trouble keeping it going the full duration.
13
  • 4th-level Spell Slots
Prepare Fabricate. Buy 50 pounds of steel for ~35gp. Spend 10 minutes casting Fabricate to turn it into a suit of full plate. Sell for 750 gp. Spend as many days making a 2000% profit as you like. Use it to finance level 14.
14
  • Magic Item Savant
  • New Infusions
    • Gem of Seeing
    • Any
  • New Cantrip:
    • Mage Hand
This is what you've been waiting through 13 levels for. Beg, borrow, steal, bribe the DM, do whatever you have to to buy two magic items. A Nature's Mantle should be relatively easy to come by at just uncommon and by now your stealth roll is d20+13+2d4 (Tireless precision and Guidance) with Advantage. Hide as a Bonus Action while lightly obscured like if you happened to also have an Eversmoking Bottle (this is optional and not the second magic item). The second item is Rare, making it notably harder to come by. But if you can get a Staff of the Woodlands you are going to be in phenomenal shape. Unless you have something better to do, you are now concentrating on Pass Without Trace at all times. I lied about your stealth earlier. It's d20+23+2d4 which averages to nearly 40. Having Invisibility as a spell is merely a formality. Also, awaken trees while you're at it because you can. You will unfortunately have to give up being attuned to the resistant armor to get both of those, but someone else might enjoy it. Mage Hand is a wonderful spell that has many uses. It'll get even better in two levels.
15
  • Perfected Armor
A free, fantastic upgrade to your attacks. I explained above why this level is so good for Infiltrator armor and I stick by it.
16
  • Feat: Telekinetic
Upgrade Mage Hand, it's now just as invisible as you are, and take the additional point of wisdom to bring yourself up to a final total of 12. You already had a good way to use your Bonus Action every round asking your homunculus for damage or help, but now you have another great option.
17
  • 5th-Level Spell slots
None of the Artificer's 5th level spells are particularly worth preparing all the time, but having the slots for upcasting is very nice.
18
  • Magic Item Master New infusions: Any two
By this point you have many options to choose from that'll get you to 6 attuned. You should make sure you always are.
19
  • Ability Score Improvement (Dex)
Nothing notable here, but you're even stealthier and better at picking locks than you were before.
20
  • Soul of Artifice
Now that's how you do a capstone. Enjoy having a functionally permanent +6 to all saves (this includes death saves in case you run out of attunements to throw under the bus).