Infinite combat phasesInfinite untap of creatures you controlInfinite mana creatures you control can produceInfinite creature LTBInfinite creature ETBInfinite death triggers
How it works
Declare Aurelia and Sandstorm Crasher as attackers, choosing to exert Sandstorm Crasher as it attacks. Aurelia and Sandstorm Crasher each trigger.
Resolve the Sandstorm Crasher trigger, creating a token copy of Aurelia that is tapped and attacking.
Put the oldest Aurelia into your graveyard due to the legend rule.
Resolve the Aurelia trigger, untapping all creatures you control and causing you to get an additional combat phase after this one.
Repeat during each combat phase using the Aurelia token instead.