Wind-Up Zenmaister [GENF-EN042] Ultimate Rare

Description

2 Level 4 monsters
This cards gains 300 ATK for each of its Xyz Materials. Once per turn, you can detach 1 Xyz Material from this card to select 1 face-up monster you control: change it to face-down Defense Position, and during the End Phase of this turn, change it to face-up Attack Position.