Survey Mechan + Mortuary + Ashnod's Altar + Desecrated Tomb + Primal Vigor

Survey Mechan

Mortuary

Ashnod's Altar

Desecrated Tomb

Primal Vigor

How it works

1. Activate Survey Mechan by sacrificing it.
2. When Survey Mechan dies, Mortuary triggers, putting Survey Mechan from your graveyard onto the top of your library.
3. Desecrated Tomb triggers, creating two creature tokens.
4. Resolve the Survey Mechan ability, dealing 3 damage to any target and causing you to draw three cards and gain 3 life.
5. Activate Ashnod's Altar twice by sacrificing the two creature tokens, adding CCCC.
6. Cast Survey Mechan by paying 4.
7. Repeat.

This clever loop relies on Survey Mechan as both the sacrificial engine and your ultimate win condition, utilizing its cost-reduction ability to make recasting it remarkably cheap. When you sacrifice Survey Mechan to Ashnod's Altar, Mortuary immediately catches it on its way to the graveyard and places it right back on top of your library for easy redrawing. Meanwhile, that departure from the graveyard triggers Desecrated Tomb, which Primal Vigor happily doubles into a pair of flying Bat tokens ready to feed right back into Ashnod's Altar for the mana needed to repeat the whole cycle.