Vigor + Deathbringer Thoctar + The Flame of Keld

Vigor

Deathbringer Thoctar

The Flame of Keld

How it works

1. At the beginning of your precombat main phase, The Flame of Keld triggers, putting a lore counter on it and increasing the amount of damage red sources you control deal by 2 this turn.
2. Activate Deathbringer Thoctar by removing a +1/+1 counter from it, putting two +1/+1 counters on it due to Vigor.
3. Activate Deathbringer Thoctar by removing a +1/+1 counter from it, dealing 2 damage to any target.
4. Repeat from step 2 as desired.