Ulalek, Fused Atrocity | Echoes of Eternity | Spawn-Gang Commander

Cards

Cast
Spawn-Gang Commander by paying ({3} magic symbol) ({R} magic symbol) ({R} magic symbol) .
Ulalek and
Spawn-Gang Commander trigger twice, and
Echoes of Eternity triggers once.
Resolve the
Echoes of Eternity trigger, copying the
Spawn-Gang Commander spell.
Resolve the copy of the
Spawn-Gang Commander spell.
Resolve one of the
Spawn-Gang Commander triggers, creating three 0/1 Eldrazi Spawn creature tokens.
Activate two Eldrazi Spawn creature tokens by sacrificing them, adding ({C} magic symbol) ({C} magic symbol) .
Resolve the copy of
Ulalek's trigger, causing you to pay ({C} magic symbol) ({C} magic symbol) to copy the
Spawn-Gang Commander spell,
Ulalek's trigger and
Spawn-Gang Commander's trigger.
Repeat from step 4.
Once you have infinite ({C} magic symbol) and Eldrazi Spawn tokens, you may sacrifice them to
Spawn-Gang Commander to deal infinite damage to any target(s).