You have cast at least three instants and/or sorceries this turn.
Steps
At the beginning of your combat phase, Rionya triggers, creating at least four token copies of Lightning Runner with haste.
Each Lightning Runner token enters the battlefield, triggering their abilities.
Resolve the first Lightning Runner trigger, adding ({E} magic symbol) ({E} magic symbol) and choosing not to pay.
Repeat step 3 until there is only one LIghtning Runner trigger remaining.
Resolve the final Lightning Runner trigger, adding ({E} magic symbol) ({E} magic symbol) and choosing to pay eight ({E} magic symbol) to untap all creatures you control and get an additional combat phase after this one.