As long as Ahsoka Tano is in any arena, Ahsoka's Protection can't be disrupted.
One of your units gets "Pay X Force Protect X (Prevent X damage to one of your other units in this arena.)" until end of turn.
Keywords
Protect
Protect X: A layered ability activated during the damage prevention POP that means, "Prevent up to X damage to one of your other units in this arena." You can play Protect only once for each instance of damage. You don't have to use all of the Protect. You choose how much damage to Protect up to X, even if the full amount of damage or more is pending.