Armed Instructor Bison

[Auto](V) Limit Break 4 (This ability is active if you have 4 or more damage): During the End Phase, if one of your 《Great Nature》 Rear-Guards was placed into your Drop Zone, choose up to 2 of your cards from the Damage Zone and turn them face-up.
[Activate](V):[CB2] Select one of your 《Great Nature》 Rear-Guards, until end of turn it gets Power +4000, at the start of the end phase of that turn, retire that unit.