Killer Queen

Stand (Must be attached to another creature, designated as it's user. Can attack Instead of
the user, but both get full combat damage.
if either one of them die, sacrifice the other.)
{3}{b} , {t}: On your upkeep only, attach a
bomb counter on target nonland permanent.
On any upkeep afterwards, you may pay {4}.
If you do, the bomb detonates and the target is destroyed. If the target leaves the battlefield in
any way, the bomb disappears.