Nim Deathmantle | Ashnod's Altar | Golgari Germination

Cards

Activate
Ashnod's Altar by sacrificing another nontoken creature, adding ({C} magic symbol) ({C} magic symbol) .
When the creature dies,
Golgari Germination and
Nim Deathmantle trigger.
Resolve the
Golgari Germination trigger, creating a 1/1 Saproling creature token.
Activate
Ashnod's Altar by sacrificing the Saproling, adding ({C} magic symbol) ({C} magic symbol) .
Resolve the
Nim Deathmantle trigger from step 2, causing you to pay ({4} magic symbol) to return the sacrificed creature from your graveyard to the battlefield, and attach
Nim Deathmantle to it.
Repeat.

This combo has been estimated to be Exhibition (Bracket 1+).