mtg from the vault legends card list Vault: Twenty From the Vault Vault, 53 cards | Magic:

The Swarmlord The Swarmlord hits the battlefield incredibly hard as a massive threat that replaces itselfand any other creature with counterswhen it dies, which poses a variety of problems for your opponents

Gargos triggers only when a spell targets one of your creatures, so you cant run the Cauldron of Souls trick

Unless ramped out early, he could easily be gone before he gets any use

With each reintroduction of the creature type, Wizards has reached deeper into the pool of keywords and mechanics for every Sliver [you control] to share

Because face-down creatures don't have a name, they can't have the same name as any other creature, even another face-down creature