Mementotlan Cranium Burst - Valiant Smashers

While you control a "Memento" monster, your opponent's monsters that can attack must attack the "Memento" monster you control with the highest ATK (their choice, if tied). When your opponent activates a monster effect on the field (except during the Damage Step): You can target 1 "Mementoal Tecuhtlica - Combined Creation" you control; it loses exactly 1000 ATK/DEF, and if it does, negate that activated effect. You can only activate this effect of "Mementotlan Cranium Burst" once per Chain.