Stalwart Successor + Umbral Collar Zealot + Furystoke Giant

Stalwart Successor

Umbral Collar Zealot

Furystoke Giant

How it works

1. Activate Umbral Collar Zealot by sacrificing Furystoke Giant
2. When Furystoke Giant dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it.
3. When Furystoke Giant enters, Stalwart Successor triggers, putting a +1/+1 counter on Furystoke Giant
4. Resolve the Umbral Collar Zealot ability.
5. Repeat.