Tyrant's Familiar [Commander 2017] Troll Set: Shards of Alara Type:

Set: Shards of Alara Type: Creature — Viashino Skeleton Rarity: Common Cost: {3}{R} {1}{B}

Whenever Siege Dragon attacks

then by all means

Set: Amonkhet Type: Sorcery Rarity: Uncommon Cost: {X}{U}{U} X target creatures can't be blocked this turn

you may sacrifice a Merfolk

Tyrant's Familiar [Commander 2017] Troll Set: Shards of Alara Type:Set: Commander 2017 Type: Creature Dragon Rarity: Rare Cost: {5}{R}{R} Flying, haste Lieutenant As long as you control your commander, Tyrant's Familiar gets +2 +2 and has "Whenever Tyrant's Familiar attacks, it deals 7 damage to target creature defending player controls." Nothing escapes its gazeor its breath.