When moving multiple readied units from base to a battlefield during a standard move, do they move simultaneously or one by one (which matters for effects like Ahri's -2 might that trigger when a unit enters)?

Ruling: When doing a standard move, multiple units can move to the same destination at the same time.

Nuances:

• This matters for effects that trigger when units enter a battlefield, as moving simultaneously means the opponent must choose which unit is affected by single-target effects like Ahri's -2 might, rather than affecting all units if they moved one by one.