Optimus Prime, Hero // Optimus Prime, Autobot Leader (Shattered Glass) [Transformers] SM201 If they don't

If they don't

Counters remain on Skullbriar as it moves to any zone other than a player's hand or library

When Toothy leaves the battlefield

Set: Sun & Moon: Burning Shadows Type: Fire Rarity: Ultra Rare Retreat cost: Colorless

Optimus Prime, Hero // Optimus Prime, Autobot Leader (Shattered Glass) [Transformers] SM201 If they don'tSet: Transformers Type: Legendary Artifact Creature Robot Rarity: Mythic Cost: {3}{U}{R}{W} More Than Meets the Eye {2}{U}{R}{W} (You may cast this card converted for {2}{U}{R}{W}.) At the beginning of each step, bolster 1. (Choose a creature with the least toughness among creatures you control and put a +1 +1 counter on it.) When Optimus Prime dies, return it to the battlefield converted under its owner's control. Reverse Type: Legendary Artifact