Hands down MKD. There were tones of little short comings with MK:DA . This new game took what was great about the new MK direction and fleshed it out into something really great. MK:DA was a shocking breakthrough for MK bringing it back from a point I doubt anything else could have survived. As big a step as it was they needed one more try to hone the concept.
I think if someone likes MK:DA better they are probably just missing thier favorite characters or something. There are a few characters and stages I would have liked to have had. The feel in the level design is different, but I have a hard time imagining anyone picking MK:DA over MKD. There is just too much more to love about it.

MK: Deception.
Basically the same kombat as Deadly Alliance and I've got some new cast to know now. And when I get tired of doing the standard fight after fight, I can open up some Puzzle Kombat, or do Chess Kombat.

MKD for sure!!!! I love the Konquest and Puzzle Kombat. With MKD you really get your money's worth. What other fighting game has all this?? It's amazing!!! The falities, harakiris, etc...Off Da Hook!!!

Mortal Kombat Deception is the best Mortal Kombat game since Mortal Kombat II. The game is just a blast to play. I cannot tell you how I love fighting Onaga with Scorpion. The game is just so much fun. Mortal Kombat Deception is my favorite of the two games.
Deadly Alliance was great but Deception just ....man...WOW