Arcanitect

Iroa abounds with beautiful architecture, magnificent statuary, cyclopean walls, and other great works. In some cases, like in the great city states, the greatest of these works have been created with the magical assistance of a cadre of Artificers called the Arcanitects.

Tool and Weapon Proficiency

Starting at 3rd level, you gain proficiency with carpenter's tools and masonry tools. If you already have either of these tool proficiencies, you gain proficiency with another kind of tool of your choice. You also become proficient with all axes, hammers, and picks, such as the battleaxe, maul, and so forth. You may apply your Intelligence modifier to your attack and damage rolls with these weapons instead of your Strength or Dexterity modifier, if it is higher.

Arcanitect Spells

You gain mold earth and shape water as artificer cantrips. Additionally, you always have certain spells prepared after you reach particular levels in this class, as shown below. These spells count as artificer spells for you, and they don't count against the number of artificer spells you prepare.
3rd / magnify gravity, tenser's floating disk
5th / shatter, spike growth
9th / erupting earth, meld into stone
13th / dimension door, gravity sinkhole
17th / telekinesis, wall of force

Masonic Rites

You gain the ability to perform certain spells as rituals that are above the spell level that you would currently or ever be able to cast as a spell, even though some of them can't normally be cast as rituals and most of them aren't on your spell list. You gain access to the following spells in this way at the class levels listed. You must use your carpentry or masonry tools as a focus when performing such rituals, depending on the medium with which you are working. You do not have the spells prepared as would usually be required to perform a ritual spell, but instead spend one or more of your Hit Dice to perform the rite, as listed below, which do not restore your hit points and are used only to fuel the ritual. You must still supply any expensive material components for any of these spells which require one. All of these spells are cast as artificer spells for you when used in this way.
3rd (1 HD) / glyph of warding, leomund's tiny hut, snare, unseen servant
5th (2 HD) / control water, fabricate, mordenkainen's private sanctum, stone shape
9th (3 HD) / creation, guards and wards, move earth, passwall
13th (4 HD) / forbiddance, mordenkainen's magnificent mansion, symbol
17th (5 HD) / demiplane, mighty fortress, temple of the gods

Demolisher

Starting at 5th level, you can invest a resonant power into axes, hammers, and picks that makes them especially destructive. This is a special infusion that doesn't count against your infusion slots, and doesn't count against the usual limit of only putting one infusion into a given item. You can have one weapon infused at a time, and may change which weapon you have infused after a short or long rest.
The infused weapon is magical, and it deals double damage to objects and structures. When you strike a creature, object or structure with this weapon, you deal +1d8 thunder damage, or +1d12 if wielded two-handed. At 15th level this increases to +2d8 / +2d12.
In someone else's hands, the weapon is less potent, and the bonus dice are d4 and d6 respectively instead of d8 and d12.

Builder

Also at 5th level, when you are building or repairing a structure or any part of a structure (a wall, a door, a bridge, etc), you get twice as much work done in a given amount of time, and can extend this benefit to a team you lead with a number of people up to your Intelligence modifier plus your relevant tool proficiency bonus.

Instant Wall

As an action, you cast wall of stone, except the wall is made of wood, has 15 hit points per inch of thickness instead of 30, and is ten 10-foot panels of 4 inches thick or twenty 10-foot panels of 2 inches thick. You can span gaps, make ramps or stairs, etc with the same restrictions as wall of stone. As with wall of stone, you may sacrifice half the length to buttress the structure, doubling its hit points and quadrupling its load capacity. Unlike wall of stone, you do not have to (and in fact cannot) concentrate to maintain the wall, but it only lasts 10 minutes before crumbling.
A freestanding 2 inch thick floor panel anchored across one side (i.e., a glorified oversized shelf) can bear a weight of 250 pounds on its flat side before breaking, while a freestanding 4 inch thick panel anchored across one side can bear a weight of 2000 pounds on its flat side. The weight capacity is doubled if the structure is anchored across at least two opposing sides; e.g., a bridge that actually makes it across a gap and thus is anchored on both sides has twice the capacity of a bridge that only goes partway across. Pilings (support pillars from the structure to bedrock beneath) and other extraneous support structures beyond buttressing cannot be created with this ability and are not included in the preceding calculation, but if you can otherwise create such a support or make use of a pre-existing support you can dramatically increase load capacity.
Additionally, you may expend spell slots to give the wall one of the following features per spell level expended. You can't spend more spell levels than your artificer class level.

• Handholds on two panels per spell level or on both sides of one panel, which can be climbed without an Athletics check, and which permit tieing things to the wall without further modification.
• Length in the form of four extra panels per spell level; this would be two panels if buttressed or if 4 inches thick, or one panel if 4 inches thick and buttressed.
• Reinforcement to increase the hit points by 50% of the base wall, and weight capacity by 100% of the base wall, per spell level.
• Slats which permit attacks to be made through the wall, at four designated 5 foot stretches per spell level; attacks against something on the other side made from farther than 5 feet away are subject to 3/4 cover.

Once you use this ability, you must take a short or long rest before you can use it again. Alternately, you can expend two hit dice as a bonus action to recharge the ability.

Applied Mathematics

At 9th level, you gain expertise on any ability check involving math or geometry. Your spells and attacks also ignore any cover or concealment less than total cover or total concealment, and you have advantage on any saving throw against an area attack or area spell if you are not incapacitated.
Correction: If you attack on your turn as part of your action, such as with a weapon or cantrip or a touch or ray spell, and you miss, you can repeat the attack roll as a bonus action. If this new attack hits, it has any and all effects it would have had you succeeded on your main action. This has no cost other than that you have now given up your bonus action for the round. 

Foreperson

Also at 9th level, when you (or you and a team you lead) work for at least 1 hour at construction or repair work, you can expend one or more spell slots to add an extra amount of work done at the rate of 2 hours of work per spell slot expended. You cannot more than double the work accomplished in this way, thus meaning you and your team got four times as much work done as usual in a given amount of time. For example, if you work by yourself for 2 hours (thus getting 4 hours of work done), you can spend at most a 2nd level spell or two 1st level spells to get an extra 4 hours of work done, meaning you did a full 8 hour day of work in only 2 hours.
Proud Wall: When you use instant wall, you can spend spell slots to make it better. You can spend 3 levels of spell slots to upgrade it to an actual wall of stone, with the same duration as the instant wall. You can spend 1 spell level to extend the duration to 1 hour, 3 spell levels to extend the duration to 1 day, or 5 spell levels to make the duration instantaneous (permanent). As noted under instant wall, you can't spend more spell levels than your artificer class level.

Wallbreaker

At 15th level, you gain a burrow speed of 15 feet while holding your demolisher, or 5 feet through solid stone. You leave a tunnel of the same diameter as your combat space (typically 5 ft). Additionally, your attacks with your demolisher ignore damage resistance to its damage type, or reduce damage immunity against that type to simple damage resistance.
Wardbreaker: You can also take an action to destroy arcane locks, glyphs of warding, symbols, walls of force or energy, and other such barriers and wards with your demolisher. To do this, expend a spell slot, and then either automatically dispel the ward or make a dispel check depending on the level of the slot sacrificed, as noted in the description of the dispel magic spell. This can destroy effects that are not normally subject to dispel magic, so long as they meet this description of a "barrier" or "ward," and so long as there is some means (e.g., disintegrate, dispel evil and good, etc) specified as able to undo the effect short of requiring a quest or a legendary item.

Architect

Also at 15th level, both your construction speed and the extra work you get from expending spell slots are doubled, including team members under your leadership.
Perfect Wall: When you use instant wall, if the structure you create would be a valid target of one of your artificer spells, you can cast that spell on it as part of the same action in which you create the structure. You must have the spell in question prepared and expend a spell slot of appropriate level to use this ability, as well as any required material components, and this counts towards the maximum spell levels you can apply to the wall.