Something that's very different, unique, with its own touch to everything.

1. There's very little explanation about the story despite a lot of really high quality cut scenes
2. The combat is turn based but also very real time due to parries, dodges, jumps and what not
3. The turn based combat is very addictive and yet very easy to understand.
4. The art, you probably have never seen stuff like you see in the game
5. The dialogues are really well thought
6. Music, fresh.

Basically, they are doing a lot of stuff that isn't what you commonly see in games yet it all works really well together.