Grenzo, Dungeon Warden + Soldevi Digger + Sengir Autocrat + Phyrexian Altar

Grenzo, Dungeon Warden

Soldevi Digger

Sengir Autocrat

Phyrexian Altar

How it works

1. Activate Phyrexian Altar by sacrificing Sengir Autocrat, adding 1.
2. When Sengir Autocrat leaves the battlefield, its second ability triggers, exiling all Serf tokens.
3. Activate Soldevi Digger by paying 2, putting Sengir Autocrat on the bottom of your library from your graveyard.
4. Activate Grenzo by paying 2, putting Sengir Autocrat into your graveyard from the bottom of your library, and then putting it onto the battlefield.
5. When Sengir Autocrat enters the battlefield, its first ability triggers, creating three 0/1 Serf creature tokens.
6. Activate Phyrexian Altar three times by sacrificing the Serfs, adding 3.
7. Repeat.