Glacial Chasm + Crucible of Worlds + Exploration

Glacial Chasm

Crucible of Worlds

Exploration

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 clever setup achieves absolute safety by treating Glacial Chasm as a completely disposable shield. Because Glacial Chasm enters the battlefield requiring you to sacrifice a land, you can use Crucible of Worlds to seamlessly replay that exact same sacrificed land right back from your graveyard. Furthermore, Exploration gives you the extra land drop necessary to pull off this loop turn after turn without falling behind on mana. When the cumulative upkeep payment becomes too steep, you simply let Glacial Chasm go to the graveyard, only to recast it immediately via Crucible of Worlds and start the prevention cycle anew.