Nim Deathmantle + Altar of Dementia + Great Whale

Nim Deathmantle

Altar of Dementia

Great Whale

How it works

1. Activate up to seven lands by tapping them, adding at least 4.
2. Activate Altar of Dementia by sacrificing Great Whale.
3. When Great Whale dies, Nim Deathmantle triggers, returning Great Whale from your graveyard to the battlefield, and attaching Nim Deathmantle to it.
4. When Great Whale enters the battlefield, it triggers, untapping up to seven lands.
5. Resolve the Altar of Dementia ability from step 2, causing target player to mill cards equal to Great Whale's power.
6. Repeat.
7. If the lands can tap to produce at least 5, this combo nets infinite mana.

This loop turns Great Whale into an endless, self-sustaining engine of revival. By feeding the whale to Altar of Dementia, you trigger Nim Deathmantle's ability to pull it right back out of the graveyard and reattach itself for a modest four-mana fee—a cost easily covered by the seven lands untapping when Great Whale re-enters the battlefield. Every cycle through this sequence grinds away your opponent's library while generating endless entry, exit, and sacrifice triggers.