It's basically a carbon copy of Y-Dragon Head given nearly identical stats and effects. The effect reads: "Once per turn during your Main Phase if you control this monster on your field you can equip this monster on one of your "X-Head Cannon" or "Y-Dragon Head" as an Equip Spell Card. OR you can change it back to a monster in face up Attack Position. When equipped to a monster by this cards effect that monster's ATK/DEF is increased by 600 points. A monster can only be equipped with one Union Monster at a time. If a monster that has this card equipped to it is destroyed, destroy this card instead."