I don't quite get your question. Technically all AGA games design to run on a standard unexpanded A1200 would be written to use its standard 2MB chip ram. There were some great looking games.
Or do you mean games released for the original OCS Amiga with 1MB, with enhanced AGA versions released?
One such example of these is Stardust.
A larger leap was for the original A500, for games utilising 1MB ram when detected, over the standard 512KB. A lot more games at that time 1987-1991 enhanced themselves in some way when the extra ram was detected. Reflections was one developer I remember showed a screen acknowledging the extra ram detected. Games such as Pinball Fantasies and Lemmings being 2 games.
As Dave stated, the leap from 512kb to 1MB was a big difference in the games. Many games were something more to offer in terms of graphics, sounds, facilities when you had 1MB of RAM. Some examples:
TV Sports Basketball gives extra speech thru the game (for example when you block your opponent you hear... "rejected" from the commentator)
Indianapolis 500 gives instant replays from multiple cameras (this option is disabled on 512k Amigas)
Hired Guns gives more sound effects with extra memory fitted
And don't forget that after a couple of years a 512KB trapdoor expansion became fairly mandatory as most new game releases in the late 80's started to state 1MB ram as the minimum requirement. Developers realised they could do so much more.
BTW, did you know that the original A1000 was shipped with just 256KB ram as a cost cutting by Commodore. In development the A1000 was meant to have 512KB as standard, and reducing this seriously restricted the OS at launch, making the ram expansion all but necessary.