Komainu Battle Armor [The List]

Menace

Equipped creature gets +2/+2 and has menace.

Whenever Komainu Battle Armor or equipped creature deals combat damage to a player, goad each creature that player controls.

Reconfigure 4 (4: Attach to target creature you control: or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)