Yamiluna the Dark Devotee

[ Warrior / ] If you have "Yamiruler the Dark Delayer" face-up on your field, you can Special Summon this card from your hand face-up to your field. [REQUIREMENT]Change the battle position of 1 face-up monster on your field. [EFFECT] Choose 1 face-up "Yamiruler the Dark Delayer" on your field. While that monster is face-up, it gains 500 ATK, and if it attacks a Defense Position monster, inflict piercing battle damage (if the ATK of the attacking monster exceeds the DEF of the attack target, inflict the difference). ATK/ 2500 DEF/ 2500