
That's a pretty solid change.Make them look like angels...or any other kind of thing. IOW, make them distant cousins of Mimics. Each gargoyle is somewhat formless until adulthood, when it takes on the form of a kind of statuary it has seen.
Make the subjects of the statues the player characters, and have the PC's take damage when the statues do.
I'm sure this is a bad idea, but it just occurred to me and I had to share.
Have every gargoyle statue they attack turn into a gargoyle. And the ones they don't just stay as statues.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.