Hello! I'm making a 2D tile based game and I need a good tool for making character animation. I were searching for a good tool but didn't found anything usable. This animation should be exported as a sprite sheet or something like that. So I don't need a vector animations tools, because it should be done in 8-bit style (check Terraria to understand what I exactly need)
What it sounds you are looking for is a pixel art tool. I would imagine Photoshop, GIMP or Paint.net or similar are often used, but you could also try something like http://tilestudio.sourceforge.net/drawing.html. Do a search on "pixel art program" or "sprite editor" for more options.