Innate Axiom is a craftable set. The 5-piece bonus adds 400 Spell and Weapon Damage to your Class abilities.
Innate Axiom is part of the Clockwork City DLC. The crafting station is located in Clockwork City (Refurbishing Yard). You can craft any armor, weapon or jewelry of this set in any motif style you know, as long as you have 2 traits researched (per item). You can trade crafted pieces to other players. Each set item becomes bound on equip.