Preston, the Vanisher, Delney, Streetwise Lookout, Sefris of the Hidden Ways, Bartolomé del Presidio, and Caves of Chaos Adventurer

Prerequisites

• Preston, the Vanisher on the battlefield
• Delney, Streetwise Lookout on the battlefield
• Sefris of the Hidden Ways on the battlefield
• Bartolomé del Presidio on the battlefield
• Caves of Chaos Adventurer in the graveyard

Steps

1. Complete a dungeon
2. Sefris' second ability triggers twice due to Delney
3. Resolve the first trigger, returning up to one other creature from your graveyard to the battlefield
4. Resolve the second trigger, returning Caves of Chaos Adventurer from your graveyard onto the battlefield
5. When Caves of Chaos Adventurer enters, it triggers once and Preston triggers twice due to Delney
6. Holding priority, activate Bartolomé del Presidio by sacrificing Caves of Chaos Adventurer
7. Resolve a Preston trigger, creating a token copy of Caves of Chaos Adventurer that is a 0/1 Illusion
8. When the Caves of Chaos Adventurer token enters, it triggers twice due to Delney
9. Resolve the Caves of Chaos Adventurer token triggers, venturing into Undercity twice
10. Resolve the second Preston trigger from step 5, creating a token copy of Caves of Chaos Adventurer that is a 0/1 Illusion
11. Repeat steps 8 and 9 one additional time
12. Resolve the Caves of Chaos Adventurer trigger from step 5, venturing into Undercity and completing Undercity
13. Repeat from step 2

Results

• Infinite +1/+1 counters on creatures you control
• Infinite ETB
• Infinite LTB
• Infinite Treasure tokens
• Infinite card draw
• Infinite colored mana
• Infinite creature tokens
• Infinite death triggers
• Infinite draw triggers
• Infinite sacrifice triggers
• Near-infinite lifeloss
• Put all basic lands from your library into your hand
• Put all creature cards from your library onto the battlefield
• Return most creature cards from your graveyard onto the battlefield