Deathbringer Thoctar + Quietus Spike

Deathbringer Thoctar
Quietus Spike

Requires
All permanents on the battlefield. Deathbringer Thoctar has at least one +1/+1 counter on it. Quietus Spike attached to Deathbringer Thoctar.
Steps
  1. Activate Deathbringer Thoctar by removing a +1/+1 counter from it, dealing 1 damage to any creature an opponent controls
  2. The creature dies as a state-based action due to Deathbringer Thoctar's deathtouch
  3. 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.