Flash! A-ah!Savior of the universe!
For no good reason other than my own amusement, occasionally I'd adapt it and substitute another single-syllable word where the "Flash!" was, to elevate the term in a ridiculous way; e.g., "Cheese! A-ah! Defender of the universe!"--although I have no recollection of using that one in particular. It's always spontaneous, tossed out in the moment when an appropriate word comes up in our conversations, as a jocular interjection, so they never stick with me.
It’s not my proudest moment as a parent, but I won’t lie: it’s up there.