"Later we will mourn those we have lost. First we must end their suffering."
—Drana, Kalastria bloodchief

Carrier Thrall

When this creature dies, create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this token: Add {C}."

The List

Commander Masters

When Carrier Thrall dies, create a 1/1 colorless Eldrazi Scion creature token. It has "Sacrifice this creature: Add {C}."

Double Masters 2022

Jumpstart: Historic Horizons

Duel Decks: Nissa vs. Ob Nixilis

When Carrier Thrall dies, put a 1/1 colorless Eldrazi Scion creature token onto the battlefield. It has "Sacrifice this creature: Add {C} to your mana pool."

Eldrazi Scions are similar to Eldrazi Spawn, seen in the Zendikar block. Note that Eldrazi Scions are 1/1, not 0/1.

Eldrazi and Scion are each separate creature types. Anything that affects Eldrazi will affect these tokens, for example.

Sacrificing an Eldrazi Scion creature token to add {C} is a mana ability. It doesn't use the stack and can't be responded to.

Some instants and sorceries that create Eldrazi Scions require targets. If all targets for such a spell have become illegal by the time that spell tries to resolve, the spell won't resolve and none of its effects will happen. You won't get any Eldrazi Scions.