Cryxis, False Blade

Equipped creature gets +3/-1 and Changeling

Whenever equipped creature deals combat damage to a player, Cryxis becomes a copy of target noncreature artifact that player controls, except it's name is "Cryxis, False Blade", it has this ability,and it has "Equipped creature gets +3/-1 and Changeling" and "Equip: Sacrifice another creature or artifact."

Equip: Sacrifice another creature or artifact

Cryxis, False Blade can be your commander