2D animation system?

Hey

Im currently working on a 2d fighting game and therefore Im creating an animation system, or at least Im planing to. But I thought it might be smarter to see if there is anything out there that matches my ideas of what the animation system should be capable of. So if know some animation systems (especially for actionscript 3) or have read some articles / books about "how to make animation systems" or anything related I would be totally happy to read it.

If some engine / framework comes to your mind just post it, but if you´re interested what I need it for, here is a short list:
- create bones on runtime and match them with verticies
- play 2d mesh / verticies based animations

thanks in advance =)
Jery

PS: The question might be a bit unclear because of my lack of experience, sorry for that.

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