Sefris of the Hidden Ways + Radiant Solar + Quicksilver Gargantuan + Moritte of the Frost

Sefris of the Hidden Ways

Radiant Solar

Quicksilver Gargantuan

Moritte of the Frost

How it works

1. Put any nontoken creature onto the battlefield.
2. When the creature enters, Radiant Solar, Quicksilver Gargantuan and Moritte of the Frost each trigger.
3. Resolve the Radiant Solar trigger, causing you to venture into Tomb of Annihilation and into the Trapped Entry room, causing each player to lose 1 life.
4. Resolve the Quicksilver Gargantuan trigger, venturing into the Oubliette room, causing you to discard a card and then sacrifice Radiant Solar.
5. Resolve the Moritte of the Frost trigger, venturing into the Cradle of the Death God room, creating a 4/4 legendary The Atropal creature token and completing Tomb of Annihilation.
6. If you control two or more The Atropal tokens, put all but one into your graveyard due to the legend rule.
7. Sefris' second ability triggers, returning Radiant Solar from your graveyard to the battlefield.
8. Repeat from step 2.

This brilliant loop turns Sefris of the Hidden Ways into a relentless dungeon master by abusing the legend rule with copy effects. When a creature enters, Radiant Solar triggers to kickstart your journey, while Quicksilver Gargantuan and Moritte of the Frost enter as clever clones that rapidly advance you through the Tomb of Annihilation. Moritte of the Frost finishes the dungeon by spawning a legendary token, and because you'll control multiple copies of that token, the legend rule immediately forces one into the graveyard. That graveyard entry triggers Sefris of the Hidden Ways's second ability to resurrect Radiant Solar right back to the battlefield, letting you seamlessly repeat the entire chain for endless venture triggers and life loss.