Astarion, the Decadent + Quietus Spike

Astarion, the Decadent
Quietus Spike

Requires
All permanents on the battlefield. Quietus Spike attached to any creature that can attack and that cannot be blocked and killed by an opponent.
Steps
  1. Deal combat damage to an opponent with the creature that has Quietus Spike attached
  2. Quietus Spike triggers, causing the opponent to lose half their life total, rounded up
  3. At the beginning of your end step, Astarion triggers, causing the opponent to lose life equal to the life they lost this turn
  4. The opponent loses the game due to having zero or less life
Results
Target opponent loses the game. Near-infinite lifeloss for target opponent.