Radiant Solar, Sefris of the Hidden Ways, Hostage Taker, and Displacer Beast

Prerequisites

• Radiant Solar on the battlefield
• Sefris of the Hidden Ways on the battlefield
• Hostage Taker in hand
• Displacer Beast on the battlefield
• available

Steps

1. Cast Hostage Taker by paying its mana cost
2. When Hostage Taker enters, it and Radiant Solar trigger
3. Resolve the Hostage Taker trigger, exiling Displacer Beast until Hostage Taker leaves the battlefield
4. Resolve the Radiant Solar trigger, venturing into the Oubliette room, causing you to discard a card and then sacrifice Hostage Taker
5. Hostage Taker leaves the battlefield, causing Displacer Beast to be returned to the battlefield from exile
6. When Displacer Beast enters, it and Radiant Solar trigger
7. Resolve the Displacer Beast trigger, venturing into the Cradle of the Death God room, creating a 4/4 legendary The Atropal creature token and completing Tomb of Annihilation
8. If you control two or more The Atropal tokens, put all but one into your graveyard due to the legend rule
9. Sefris' second ability triggers, returning Hostage Taker from your graveyard to the battlefield
10. When Hostage Taker enters, it and Radiant Solar trigger
11. Resolve the Hostage Taker trigger, exiling Displacer Beast until Hostage Taker leaves the battlefield
12. 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
13. Resolve the Radiant Solar trigger from step 6, venturing into the Oubliette room, causing you to discard a card and then sacrifice Hostage Taker
14. Repeat from step 5

Results

• Near-infinite ETB
• Near-infinite LTB
• Near-infinite death triggers
• Near-infinite lifeloss for all players
• Near-infinite sacrifice triggers