“{1, 2, 3} and {4, 5, 6}”

Letters accompanying applications, for short

Includes without others knowing, in a way

"I haven't a clue"

Plant with an edible inner gel

Up to snuff

All over the place

Drove in an A.T.V., say, informally

Fighting technique used by [circled letters] (as explained at 76-Across)

Unreal?