Guardian of Primus

A plane of utmost order, Mechanus is a realm overseen by a godlike entity called Primus, whose actions are inscrutable and calculations, vast. You have dedicated your life to the machinations of the leader of the modrons. You have taken a solemn vow to serve Primus in both life and death, for in return you have been granted the logic required to call on the modrons at a moments notice.

In service to Primus, you have been gifted with the knowledge of numerous conjuration and transmutation spells. Furthermore, the power of Mechanus infuses these spells with clockwork machinations. The cost for this service is that you continually become more infused with clockwork each time you gain a level in this class. If you reach level 20 in this class, your body, regardless of what race you are, will take on the appearance of a large modron, similar to your original form. You maintain all of the aspects and features of your race.

Clockwork Familiar

1st-level Guardian of Primus feature

As part of your connection to Mechanus, or perhaps as a gift from Primus himself, a tiny clockwork familiar follows you everywhere. You may use the find familiar spell at will and without expending any spell slots. Use one of the stats as required in the spell, but instead of the familiar taking on the the form of a magical creature, consider how it would look in clockwork form. You may roll on the Clockwork Familiar table to determine what its features are.

D6	Clockwork Familiar
1	Instead of one familiar, this one appears as two (sharing a single stat sheet). The two argue constantly over the most logical solution to every problem.
2	The hands of a clock appear in its eyes, and the sounds of ticking can be heard while near it. The familiar always knows the time of day and which way is north.
3	It's surface glows with a golden, metallic sheen and can serve as a source of light.
4	It's features are unnaturally angular, like geometric objects. People would pay good money just to look at it up close.
5	It carries a small wand and wears a wizard's hat. Once per short rest it may cast a spell that you know, expending your spell slot.
6	The familiar is always listening to what goes on around it and can accurately recall any information either of you heard in the past 30 days.

Tool Profciency

3rd-level Guardian of Primus feature

When you adopt this specialization at 3rd level, you gain proficiency with Smith's Tools. If you already have this proficiency, you gain expertise instead. If you ever gain expertise with Smith's Tools from another source, including the Artificer main class features, you gain the unique tool proficiency of Genius. A Genius proficiency with Smith's Tools automatically grants a critical success of 20, plus your proficiency bonus and Intelligence modifier, on every roll associated with checks where the Smith's Tools can be used.

Hammer of Primus

3rd-level Guardian of Primus feature

Starting at 3rd level, your smith's tools are more than mere hardware. While using these tools you can feel the power of Primus surging through you and his strength flows into your craft. During combat is when these powers seem to be especially effective. You may use your smith's tools as an action to hammer out the kinks in any metal armor, granting allies a bonus to their AC until the start of your next turn. If the creature is wearing leather armor, this action will grant the benefits of studded leather armor until the start of your next turn. Hammer of Primus gains additional features at 4th, 8th, 12th, 16th, and 20th level.

Mechanus Magic

3rd-level Guardian of Primus feature

Your connection with Mechanus and your sworn duty to protect the ideas of Primus, by restoring order to the battlefield, has granted you access to additional spells focused on control and protection. 

Starting at 3rd level, you always have certain spells prepared after you reach particular levels in this class, as shown in the Mechanus Magic table. These spells count as artificer spells for you, but they don’t count against the number of artificer spells you prepare. Additionally, when you cast a Mechanus Magic you must use the mandatory exceptions listed in the Modron Control feature.

Mechanus Magic

Artificer Level	Spell
3rd	entangle, bless
5th	spike growth, warding bond
9th	slow, counterspell
13th	grasping vine, resilient sphere
17th	arcane hand, wall of force

Construct Summoner

3rd-level Guardian of Primus feature

By 3rd level, your connection with Mechanus allows you to summon constructs to aid you in battle. Refer to the Construct Summons table for the list of constructs available at each level. These summoned constructs can act autonomously, be verbally commanded to complete a single task, or can be controlled directly using a bonus action. All summoned constructs last until they are killed, you take a long rest, or you dismiss them with a free action. You determine the construct to be summoned according to your level and types of constructs available.

Thanks to your vast knowledge of the order and logic of the modrons, your summoned constructs may also be used to maintain concentration on your spells, allowing multiple concentration spells to be active at one time.

You gain additional creatures to summon at 5th, 9th, 13th, 17th level. When you summon a construct of your own choosing, it must be of a CR equal to or less than your Artificer level. At 20th-level, the CR requirement for your 2 additional summoned constructs can be ignored, additionally, all of your constructs can last for 72 hours. 

Construct Summons

ARTIFICER LEVEL	Constructs
3rd	1ea flying sword
5th	2ea flying sword, 1ea animated armor, 1ea construct of your choosing.
9th	3ea flying sword, 2ea animated armor, 1ea construct of your choosing.
13th	4ea flying sword, 3ea animated armor, 1ea construct of your choosing.
17th	4ea flying sword, 3ea animated armor, 2ea construct of your choosing.

Primus Revivus

9th-level Guardian of Primus feature

Once per long rest you can rebuild a dead ally. 

You may cast the reincarnate spell at will once per long rest. It does not count against your spells known and does not expend a spell slot to cast. Those who are brought back become a modron infused replica of their original form and no one rolls on the table listed in the spell. The effected humanoid has their alignment set to Neutral and is considered a construct which can no longer be healed - but it can be mended.

Font of Knowledge

15th-level Guardian of Primus feature

Pick any two spells known to you of first level or higher. Your Font of Knowledge spells may be cast at will without expending a spell slot once each per long rest. At teh end of a long rest you may keep the same two spells or replace one or both.

You may learn an additional spell to add to your Artificer Spells list. It must be of a level for which you have access to. The spell can be picked from any class list but must be a Conjuration or Transmutation spell. Once learned, it becomes an Artificer spell for you. Hereafter, every time you gain a level in this class you may pick one additional spell following the rules above.

Modron Control

Use the power of the modrons to control the battlefield and alter existing spells in glorious machinations. Whenever you cast a spell from the Primus Magic table, that spell becomes infused with modrons. Any Fire, Cold, or Poison damage from these spells is converted to Force damage. Additionally, the visual description of the spell can be altered to fit the clockwork thematic. Furthermore, any of the spells listed on the Primus Magic table that require concentration may have their concentration shifted to any of your summoned constructs as a bonus action.

Follow the example of this Primus Entangle Spell:

Sharp wires controlled by tiny modrons burst into the current plane in a 20-foot square starting from a point within range. For the duration, these constructs turn the ground in the area into difficult terrain.

A creature in the area when you cast the spell must succeed on a Strength saving throw or be restrained by the entangling wires until the spell ends. A creature restrained by the wires can use its action to make a Strength check against your spell save DC. On a success, it frees itself.

When the spell ends, the conjured constructs rust away.

Your summoned Flying Sword may be granted the concentration on this spell as a bonus action after casting it.