Malcolm, Keen-Eyed Navigator + Amoeboid Changeling + Weftstalker Ardent

Malcolm, Keen-Eyed Navigator

Amoeboid Changeling

Weftstalker Ardent

How it works

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

This ingenious loop turns a trickle of artifacts into an absolute tidal wave by cleverly rewriting creature types. With Malcolm, Keen-Eyed Navigator on board, every instance of your opponents taking damage from a Pirate normally creates Treasure, but Weftstalker Ardent isn't naturally a member of the crew. That’s where Amoeboid Changeling steps in, granting Weftstalker Ardent every creature type—including Pirate—so that its own damage-dealing ability satisfies Malcolm's condition. Every time an artifact enters the battlefield, Weftstalker Ardent triggers to singe your opponents, which in turn prompts Malcolm to yield a fresh crop of Treasure tokens; because those Treasures are artifacts entering the battlefield, they restart Weftstalker Ardent's damage trigger all over again, sustaining an infinite cascade of pings, mana, and tokens.