Cast Glorious Protector by paying its mana cost.
When Glorious Protector enters, it and Radiant Solar trigger.
Resolve the Glorious Protector trigger, exiling Bloodboil Sorcerer until Glorious Protector leaves the battlefield.
Resolve the Radiant Solar trigger, venturing into the Oubliette room, causing you to discard a card and then sacrifice Glorious Protector.
Glorious Protector leaves the battlefield, causing Bloodboil Sorcerer to be returned to the battlefield from exile.
When Bloodboil Sorcerer enters, it and Radiant Solar trigger.
Resolve the Bloodboil Sorcerer trigger, venturing into the Cradle of the Death God room, creating a 4/4 legendary The Atropal creature token and completing Tomb of Annihilation.
If you control two or more The Atropal tokens, put all but one into your graveyard due to the legend rule.
Sefris' second ability triggers, returning Glorious Protector from your graveyard to the battlefield.
When Glorious Protector enters, it and Radiant Solar trigger.
Resolve the Glorious Protector trigger, exiling Bloodboil Sorcerer until Glorious Protector leaves the battlefield.
Resolve the Radiant Solar trigger from step 10, venturing into Tomb of Annihilation and into the Trapped Entry room, causing each player to lose 1 life.
Resolve the Radiant Solar trigger from step 6, venturing into the Oubliette room, causing you to discard a card and then sacrifice Glorious Protector.
Repeat from step 5.
Cast [[Permanent with ETB: "Exile a creature" and LTB: "Return exiled creature to BF" (Banish Creature)|banisher]] by paying its mana cost.
When Glorious Protector enters, it and Radiant Solar trigger.
Resolve the Glorious Protector trigger, exiling Radiant Solar and two other nontoken creatures until Glorious Protector leaves the battlefield.
Resolve the Radiant Solar trigger, venturing into the "Sandfall Cell" room, causing you to sacrifice Glorious Protector and each opponent to either sacrifice a creature, artifact or land or lose 2 life.
Glorious Protector leaves the battlefield, returning Radiant Solar and the two other nontoken creatures from exile to the battlefield.
Radiant Solar and the two creatures enter the battlefield, triggering Radiant Solar three times.
Resolve the first Radiant Solar trigger, venturing into the "Cradle of the Death God" room, creating a 4/4 The Atropal legendary creature token, and completing Tomb of Annihilation.
Sefris' second ability triggers, returning Glorious Protector from your graveyard to the battlefield.
When Glorious Protector enters, it and Radiant Solar trigger.
Resolve the Glorious Protector trigger, exiling Radiant Solar and two other nontoken creatures until Glorious Protector leaves the battlefield.
Resolve the Radiant Solar trigger, venturing into the "Trapped Entry" room of the Tomb of Annihilation, causing each player to lose 1 life.
Resolve the second Radiant Solar trigger from step 6, venturing into the "Veils of Fear" room, causing each player to lose 2 life unless they discard a card.
Repeat from step 4.

Near-infinite ETB

Near-infinite LTB

Near-infinite blinking

Near-infinite death triggers

Near-infinite lifeloss for all players

Near-infinite sacrifice triggers

Radiant Solar

Sefris of the Hidden Ways

Glorious Protector

Bloodboil Sorcerer

Cast Faceless Butcher by paying its mana cost.
When Faceless Butcher enters, it and Radiant Solar trigger.
Resolve the Faceless Butcher trigger, exiling Bloodboil Sorcerer.
Resolve the Radiant Solar trigger, venturing into the Oubliette room, causing you to discard a card and then sacrifice Faceless Butcher.
When Faceless Butcher dies, it triggers, returning Bloodboil Sorcerer from exile to the battlefield.
When Bloodboil Sorcerer enters, it and Radiant Solar trigger.
Resolve the Bloodboil Sorcerer trigger, venturing into the Cradle of the Death God room, creating a 4/4 legendary The Atropal creature token and completing Tomb of Annihilation.
If you control two or more The Atropal tokens, put all but one into your graveyard due to the legend rule.
Sefris' second ability triggers, returning Faceless Butcher from your graveyard to the battlefield.
When Faceless Butcher enters, it and Radiant Solar trigger.
Resolve the Faceless Butcher trigger, exiling Bloodboil Sorcerer.
Resolve the Radiant Solar trigger from step 10, venturing into Tomb of Annihilation and into the Trapped Entry room, causing each player to lose 1 life.
Resolve the Radiant Solar trigger from step 6, venturing into the Oubliette room, causing you to discard a card and then sacrifice Faceless Butcher.
Repeat from step 5.

Faceless Butcher

Complete a dungeon.
Sefris' second ability triggers twice due to Delney.
Resolve the first trigger, returning up to one other creature from your graveyard to the battlefield.
Resolve the second trigger, returning Bloodboil Sorcerer from your graveyard onto the battlefield.
When Bloodboil Sorcerer enters, it triggers once and Preston triggers twice due to Delney.
Holding priority, activate Thermopod by sacrificing Bloodboil Sorcerer.
Resolve a Preston trigger, creating a token copy of Bloodboil Sorcerer that is a 0/1 Illusion.
When the Bloodboil Sorcerer token enters, it triggers twice due to Delney.
Resolve the Bloodboil Sorcerer token triggers, venturing into Undercity twice.
Resolve the second Preston trigger from step 5, creating a token copy of Bloodboil Sorcerer that is a 0/1 Illusion.
Repeat steps 8 and 9 one additional time.
Resolve the Bloodboil Sorcerer trigger from step 5, venturing into Undercity and completing Undercity.
Repeat from step 2.

Combos with "Bloodboil Sorcerer"