i want to build 2d game…how can i make the character move such as kick or punch?? i been using javascript…
I would not recommend using Unity3D for a 2D game, the sprite handling is aweful. Try using GameMaker for this one.
To make 2D animations; simply draw them. Draw every frame and put them together in a .gif file.
You can use Pencil to create these animations.
Actually Unity is as good as any for sprites, just ignore the z-axis and start creating awesomeness. :-)
It's just a matter of setting up the tools you need for your implementation, animating from sprite sheets is really easy. Here's an example how to switch between different states in sprite sheets. Just create a single polygon plane and reuse it for all your characters.
Not only will you have total freedom if you for instance want to have something in 3d, you'll also have one of the most powerful physics engines on the market and perhaps the easiest pipeline there is.