Malcolm, Keen-Eyed Navigator + Amoeboid Changeling + Ingenious Artillerist

Prerequisites

• You have a way to cause an artifact to enter the battlefield under your control.

Steps

1. 1Activate Amoeboid Changeling by tapping it, giving Ingenious Artillerist all creature types until end of turn.
2. 2Cause an artifact to enter the battlefield under your control.
3. 3Ingenious Artillerist triggers, dealing 1 damage to each opponent.
4. 4Malcolm triggers, as Ingenious Artillerist is a Pirate due to Amoeboid Changeling, creating a Treasure token for each opponent dealt damage this way.
5. 5When the Treasure(s) enter, Ingenious Artillerist triggers that many times.
6. 6Resolve the first Ingenious Artillerist trigger, dealing 1 damage to each opponent.
7. 7Repeat from step 4.

Effects

• Infinite colored mana
• Infinite damage
• Infinite Treasure tokens