Glacial Chasm + Perennial Behemoth + Wayward Swordtooth

Glacial Chasm

Perennial Behemoth

Wayward Swordtooth

How it works

1. Play Glacial Chasm either from your hand or from your graveyard.
2. When Glacial Chasm enters the battlefield, its second ability triggers, causing you to sacrifice another land you control.
3. Play any land from your graveyard.
4. At the beginning of your next upkeep, Glacial Chasm's cumulative upkeep ability triggers, allowing you to choose not to pay the cost and sacrifice it instead.
5. Repeat.

This ingenious engine keeps you entirely immune to damage by constantly cycling your lands, using Glacial Chasm to blank all incoming harm while sacrificing itself to avoid paying its mounting cumulative upkeep costs. To sustain this loop, Perennial Behemoth allows you to replay that sacrificed land straight from your graveyard turn after turn. Meanwhile, Wayward Swordtooth provides the extra land drop necessary each turn to ensure your economy keeps pace, completely mitigating the self-sacrificing drawback of Glacial Chasm into an unbreakable defensive lock.