Sin, Unending Cataclysm + Body of Research + Sage of Hours

Prerequisites

• You have a way to kill a creature.

Steps

1. 1Cast Body of Research by paying , creating a 0/0 Fractal creature token and putting a number of +1/+1 counters on it equal to your deck size.
2. 2Cast Sin either from your hand or from the command zone by paying plus commander tax if applicable. As it enters, remove all the counters from the Fractal and put twice that many +1/+1 counters on Sin.
3. 3Kill Sin. When it dies, it second ability triggers, putting its counters on Sage of Hours and shuffling Sin into your library.
4. 4Activate Sage of Hours by removing all +1/+1 counters from it, causing you to get an extra turn for each five +1/+1 counters removed from it.

Effects

• Lock
• Near-infinite turns