Sage of Hours + Extruder + Myr Battlesphere + Karador, Ghost Chieftain

Sage of Hours

Extruder

Myr Battlesphere

Karador, Ghost Chieftain

How it works

1. Cast Myr Battlesphere from your graveyard by paying 7.
2. When Myr Battlesphere enters, it triggers, creating four 1/1 Myr artifact creature tokens.
3. Activate Extruder five times by sacrificing Myr Battlesphere and the four Myr tokens, 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.