Goblin Biker Troika Griare

2+ Level 3 monsters While 3 or more Xyz Materials are attached to monsters on the field, "Goblin" monsters you control can attack directly. Once per turn, if a monster(s) is Normal or Special Summoned, while this card is in the Monster Zone (except during the Damage Step): You can target 1 of those monsters; detach 1 material from a monster on either field, and if you do, change the targeted monster's battle position. Once per turn, when an opponent's monster declares an attack: You can detach 1 material from a monster on either field, and if you do, negate that attack.