Unspeakable Symbol + Sage of Hours + Gray Merchant of Asphodel + Thassa, Deep-Dwelling

Unspeakable Symbol

Sage of Hours

Gray Merchant of Asphodel

Thassa, Deep-Dwelling

How it works

1. At the beginning of your end step, Thassa triggers, blinking Gray Merchant of Asphodel.
2. When Gray Merchant of Asphodel enters the battlefield, it triggers, causing each opponent to lose life equal to your devotion to black, and you to gain life equal to the life lost this way.
3. Activate Unspeakable Symbol five times by paying 15 life, putting five +1/+1 counters on Sage of Hours.
4. Activate Sage of Hours by removing all +1/+1 counters from it, causing you to take at least one extra turn after this one.
5. Repeat each turn.