Using advanced knowledge of biology, they have formed a symbiotic bond with a mechanical being that can assist in integrating the traits of those that it absorbs. This bond allows the Xenografter to harvest and preserve the abilities of slain creatures, making them a versatile and adaptive combatant.

Tool Proficiency

3rd-level Xenografter feature

You gain proficiency with cook's utensils. If you already have this proficiency, you gain proficiency with one other type of artisan’s tools of your choice.

Xenografter Spells

3rd-level Xenografter feature

You always have certain spells prepared after you reach particular levels in this class, as shown in the Xenografter Spells table. These spells count as artificer spells for you, but they don’t count against the number of artificer spells you prepare.

Battle Smith Spells

Artificer Level	Spell
3rd	disguise self, absorb elements
5th	spider climb, alter self
9th	vampiric touch, gaseous form
13th	polymorph, blight
17th	contagion, hold monster

Symbiotic Infusion

3rd-level Xenografter feature

Your creation of a symbiotic being, bonded to you has granted you new unique abilities. This grants the following traits:

• You gain proficiency with Medicine, and may choose to substitute your Intelligence bonus in place of Wisdom when making Medicine checks.

Integrating a trait: If you spend one hour of study and preparation (this can be done during a short or long rest) over the corpse of a creature who died in the last 24 hours, you can attempt to separate one of its traits from the body and integrate it to yourself. You can't integrate traits from constructs or undead.
The result of your experiment is decided by a Medicine check (DC for which is 10 + the creatures CR, minimum of 1). On a success, the DM selects up to 3 traits from the dead creature, from these 3 you choose one of the traits for your symbiote to integrate. 

Eligible traits: Traits include: Damage Resistances, Natural Weapons, Sense, and Abilities. If the selected trait requires Attack Rolls or Saving Throws, you can use your spell attack modifier and spell save DC respectively. If the ability has a recharge or a specified number of uses, you can only use it once. Integrated traits are removed when you finish a long rest or when you use this ability again.

Preserving a trait: When you finish a long rest while bearing a trait, you can choose to preserve it as an infused item. The trait then lasts for as long as you don't end the infusion, and any uses of the trait are recovered when you finish a long rest.

Extra Attack

5th-level Xenografter feature

You can attack twice, rather than once, whenever you take the Attack action on your turn.

Rapid Integration

9th-level Xenografter feature

You can utilize your symbiote to integrate a trait from a living creature in the heat of combat. As an action you can attempt to steal a creatures sense or damage resistance of your choice. The creature must make a Constitution saving throw against your spell save DC. On a failure, you integrate the chosen trait, while the creature loses it for 1 minute.
You can use this feature a number of times equal to your proficiency bonus, recharging on a long rest.

Perfect Symbiosis

15th-level Xenografter feature

When you preserve a trait, you also learn how to recreate it as an infusion permanently. You can then add that trait as an infusion you know, in place of another one of your infusions known. 
You can also increase the number of infusion known and infused items you have by 2, but those extra infusions must be preserved traits.

Finally, when you would integrate a trait from a dead creature, you can now choose 2 to integrate instead of 1.