Sefris of the Hidden Ways + Radiant Solar + Quicksilver Gargantuan + Synth Infiltrator

Sefris of the Hidden Ways

Radiant Solar

Quicksilver Gargantuan

Synth Infiltrator

How it works

1. Put any nontoken creature onto the battlefield.
2. When the creature enters, Radiant Solar, Quicksilver Gargantuan and Synth Infiltrator 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 Synth Infiltrator 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 looping engine transforms the classic Tomb of Annihilation into a devastating perpetual motion machine by turning simple creature entries into immediate dungeon completion. As you cycle creatures through the loop, Radiant Solar reliably triggers to push you deeper into the dungeon while also serving as the crucial recurring payoff brought back by Sefris of the Hidden Ways' graveyard mastery. Meanwhile, Quicksilver Gargantuan and Synth Infiltrator act as shape-shifting catalysts that rapidly accelerate your progression through the rooms, ultimately sacrificing the Solar and triggering the legend rule on the resulting tokens to feed Sefris's recursion cleanly.