Deathbringer Thoctar, and Horobi, Death's Wail

Prerequisites

• Deathbringer Thoctar on the battlefield
• Horobi, Death's Wail on the battlefield
• Deathbringer Thoctar has at least one +1/+1 counter on it

Steps

1. Activate Deathbringer Thoctar by removing a +1/+1 counter from it, targeting any creature an opponent controls
2. Horobi triggers, destroying the targeted creature
3. When the creature dies, Deathbringer Thoctar triggers, putting a +1/+1 counter on itself
4. Repeat as desired
5. You may also repeat this combo whenever a creature enters the battlefield under an opponent's control

Results

• Destroy all creatures opponents control
• Destroy any creature that enters the battlefield under an opponent's control