...suit, armor... something, to save Bruce/Batman ass :P ?

IIRC yes

@arkhamwrath said:

Go read Injustice! I won't spoil it for you

It happened in Alvin and the Chipmunks. No, seriously. There was an Alvin and the Chipmunks Batman parody, I had it on VHS. Simon was Batman, Theodore was Alfred, and Alvin was the Joker. Simon and his love interest were captured, so Theodore rescued them. As Batman. Kind of. I don't remember it that well.

He did it in Batman: The Long Shadows...sort of. This was when Dick was Batman immediately after Battle For the Cowl but he was still pretty green, and this caused Two-Face to ambush him in his new Batcave. Two-Face had Dick at his mercy and didn't believe that he was the real Batman, so Alfred wore a Batman mask and used some sophisticated trickery to trick Dent that he was indeed the real Batman, giving Dick the opportunity to take down Two-Face.