Magmatic Galleon + Mayhem Devil

Prerequisites

• An opponent controls an indestructible creature, or you have a way to give an opponent's creature indestructible.
• You control a number of Treasure tokens greater than the indestructible creature's toughness.

Steps

1. 1Give an opponent's creature indestructible, if needed.
2. 2Activate a Treasure token by sacrificing it, adding one mana of any color.
3. 3Mayhem Devil triggers, dealing 1 damage to the indestructible creature.
4. 4If the creature has less than 0 toughness, Magmatic Galleon's second ability triggers, creating a Treasure artifact token.
5. 5Repeat from step 2.

Effects

• Infinite colored mana