Although Sierra was the first with their so-called "3D Adventure Game", there are a dozen of clones made since...
To set some facts straight, these games are NOT AGI or SCI (but ARE related to Sierra):
- Dynamix games: Willy Beamish, Rise of the Dragon & Heart of China, etc.
- (Some) Sierra action-games: Oil's Well (remake), The Incredible Machine series, etc.
- GameArts games: Thexder, Firehawk, Silpheed, etc.
- Coktel Vision games: Gobliiins, Gobliins, Ween, etc.
- 3D Helicopter Simulator (only the demo is in AGI)
- Winnie the Pooh & Mickey's Space Adventure (despite earlier claims, these are NOT AGI, both use a different engine)
Not AGI/SCI, nor related to Sierra (AFAIK):
- Hugo Series
- Accolade adventures: Les Manley series, Altered Destiny (use a VERY similiar engine, got sued for it)
- The game(s?) some Sierra programmers made when they left Sierra and formed Tsunami (ok, maybe a bit related...)