Goblin Biker Big-Head Gabonga

2 Level 3 monsters
If this card is Xyz Summoned: You can add 1 "Goblin" monster from your Deck to your hand. If a material(s) is detached from a monster(s) on the field (except during the Damage Step): You can target 1 other face-up monster on the field; attach it to this card as material. During the End Phase: You can attach 1 "Goblin" monster from your Deck to this card as material. You can only use each effect of "Goblin Biker Big-Head Gabonga" once per turn.