Sage of Hours + Master Biomancer + Conjurer's Closet

Sage of Hours

Master Biomancer

Conjurer's Closet

How it works

1. At the beginning of your end step, Conjurer's Closet triggers, blinking Sage of Hours and causing it to enter the battlefield with five or more +1/+1 counters on it due to Master Biomancer.
2. Activate Sage of Hours by removing all +1/+1 counters from it, causing you to take at least one extra turn after this one.
3. Repeat each turn.