Sage of Hours + The Ten Rings + Prognostic Sphinx + Stark's Ingenuity

Sage of Hours

The Ten Rings

Prognostic Sphinx

Stark's Ingenuity

How it works

1. If you have six or more cards in hand, activate Prognostic Sphinx by discarding a card.
2. Repeat step 1 until you have five or fewer cards in hand.
3. At the beginning of your end step, The Ten Rings triggers, causing you to draw cards until you have ten cards in your hand.
4. Stark's Ingenuity triggers for each card drawn, putting that many +1/+1 counters on Sage of Hours.
5. Activate Sage of Hours by removing all +1/+1 counters from it, causing you to take at least one extra turn after this one.
6. Repeat each turn.