Cast Myr Battlesphere by paying {7}.
Myr Battlesphere enters the battlefield, triggering itself and Genesis Chamber.
Resolve the Myr Battlesphere trigger, creating four 1/1 Myr artifact creature tokens.
Resolve the Genesis Chamber trigger, creating a 1/1 Myr artifact creature token.
Activate Krark-Clan Ironworks five times by sacrificing the Myr tokens, adding ten {C}.
Activate Mirage Mirror by paying {2}, targeting Myr Battlesphere.
Cowardice triggers, returning Myr Battlepshere from the battlefield to your hand.
Mirage Mirror's ability fails to resolve  due to no longer having a legal target.
Repeat.

Infinite colorless mana

Infinite creature tokens

Infinite death triggers

Infinite creature ETB

Infinite creature LTB

Infinite creature sacrifice triggers

Infinite storm count

Cowardice

Mirage Mirror

Myr Battlesphere

Krark-Clan Ironworks

Genesis Chamber

Cast Myr Battlesphere by paying {7}.
Myr Battlesphere enters the battlefield, triggering itself and Genesis Chamber.
Resolve the Myr Battlesphere trigger, creating four 1/1 Myr artifact creature tokens.
Resolve the Genesis Chamber trigger, creating a 1/1 Myr artifact creature token.
Activate Ashnod's Altar five times by sacrificing the Myr tokens, adding ten {C}.
Activate Mirage Mirror by paying {2}, targeting Myr Battlesphere.
Cowardice triggers, returning Myr Battlepshere from the battlefield to your hand.
Mirage Mirror's ability fails to resolve  due to no longer having a legal target.
Repeat.

Ashnod's Altar

Cast Myr Battlesphere by paying at most {4}.
Myr Battlesphere enters the battlefield, creating four 1/1 Myr artifact creature tokens.
Activate Krark-Clan Ironworks three times by sacrificing the Myr tokens, adding six {C}.
Activate Mirage Mirror by paying {2}, targeting Myr Battlesphere.
Cowardice triggers, returning Myr Battlepshere from the battlefield to your hand.
Mirage Mirror's ability fails to resolve  due to no longer having a legal target.
Repeat.

Mycosynth Golem

Cast Myr Battlesphere by paying at most {4}.
Myr Battlesphere enters the battlefield, creating four 1/1 Myr artifact creature tokens.
Activate Ashnod's Altar three times by sacrificing the Myr tokens, adding six {C}.
Activate Mirage Mirror by paying {2}, targeting Myr Battlesphere.
Cowardice triggers, returning Myr Battlepshere from the battlefield to your hand.
Mirage Mirror's ability fails to resolve  due to no longer having a legal target.
Repeat.

Activate Lightning Greaves' equip ability by paying {0}, targeting Priest of Gix.
Cowardice triggers, returning Priest of Gix from the battlefield to your hand.
Cast Priest of Gix by paying {2}{B}.
Priest of Gix enters the battlefield, adding {B}{B}{B}.
Repeat.

Lightning Greaves

Priest of Gix

Activate Lightning Greaves' equip ability by paying {0}, targeting Priest of Urabrask.
Cowardice triggers, returning Priest of Urabrask from the battlefield to your hand.
Cast Priest of Urabrask by paying {2}{R}.
Priest of Urabrask enters the battlefield, adding {R}{R}{R}.
Repeat.

Priest of Urabrask

Tezzeret, Master of the Bridge

Activate Lightning Greaves' equip ability by paying {0}, targeting Burning-Tree Emissary.
Cowardice triggers, returning Burning-Tree Emissary from the battlefield to your hand.
Cast Burning-Tree Emissary by paying {R/G}{R/G}.
Burning-Tree Emissary enters the battlefield, adding {R}{G}.
Repeat.

Burning-Tree Emissary

Activate Lightning Greaves' equip ability by paying {0}, targeting Hidden Herbalists.
Cowardice triggers, returning Hidden Herbalists from the battlefield to your hand.
Cast Hidden Herbalists by paying {1}{G}.
Hidden Herbalists enters the battlefield, adding {G}{G}.
Repeat.

Combos with "Cowardice"