Resolve the first trigger, returning up to one other creature from your graveyard to the battlefield.
Resolve the second trigger, returning
Veteran Dungeoneer from your graveyard onto the battlefield.
When
Veteran Dungeoneer enters, it triggers once and
Preston triggers twice due to
Delney.
Resolve a
Preston trigger, creating a token copy of
Veteran Dungeoneer that is a 0/1 Illusion.
When the
Veteran Dungeoneer token enters, it triggers twice due to
Delney.
Resolve the first
Veteran Dungeoneer token trigger, venturing into Tomb of Annihilation and into the Trapped Entry room, causing each player to lose 1 life.
Resolve the second
Veteran Dungeoneer token trigger, venturing into the Oubliette room, causing you to discard a card and then sacrifice the nontoken
Veteran Dungeoneer.
Resolve the second
Preston trigger from step 5, creating a token copy of
Veteran Dungeoneer that is a 0/1 Illusion.
When the
Veteran Dungeoneer token enters, it triggers twice due to
Delney.
Resolve the first
Veteran Dungeoneer token 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.
Repeat from step 2.
Results
Near-infinite lifegain triggers.
Near-infinite lifeloss.
Near-infinite lifeloss for all players.
Near-infinite creature sacrifice triggers.
Near-infinite ventures into the dungeon.
Return most creature cards from your graveyard onto the battlefield.
Cast a subset of spells in your library.
Near-infinite +1/+1 counters.
Near-infinite creature ETB.
Near-infinite creature LTB.
Near-infinite Treasure tokens.
Near-infinite card draw.
Near-infinite colored mana.
Near-infinite creature tokens.
Near-infinite death triggers.
Near-infinite draw triggers.
Near-infinite lifegain.
Metadata
Bracket tag
ExhibitionBracket 1+
For any deck
1
2
3
4
5
1 · Exhibition5 · cEDH
Bracket tags are estimated from the cards and results of each combo, as a guideline rather than a strict classification.