Does anyone know a good sprite-making tool/program that I can use to make nice looking sprites?
Well, theres spriter from brashmonkey.
For the sprite making, I'd say use photoshop for making sprites. If you have the budget, you can purchase spriter for like 60 bucks. Other wise, go here(https://www.slant.co/topics/1561/~2d-an ... evelopment) for sprite animation softwares.
The spriter i mention is an animation software for your sprites, but still, use photoshop for making sprites.
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I recommend Fireworks. The software able to handle raster & vector manipulation and also provide simple animation editor. Good enough for me for it's capability.