The Mortal Kombat games releases go like this. Mortal Kombat, MK2, MK3. Then I think MK trilogy(all the games put together plus some other characters for PS1) and Ultimate MK3(MK3 with more characters for SNES) came out at the same time. Then Mortal Kombat 4 came out, which was the last MK game to be made for arcade and the first 3D game in the series. Next came Mortal Kombat Gold for Dreamcast which I belive was MK4, maybe with some extra character/stages. Mortal Kombat: Deadly Alliance came out in 2002. It's a pretty decent fighter, but it's outshined by games like Soul Calibur 2. I'd say this is worth the $20 it costs now for the unlockables. Things like Concept Art, old posters, comics, and a funny as hell video called cooking with scorpian. Also in the next couple of months a new MK game is coming out for PS2 and Xbox. I think its called Mortal Kombat: Deception. It will also come out on GCN sometime next year.