I don't think so.But if you went through the process of copyrighting the image, it'd be illegal.
But technically speaking, the minifig design is already copyrighted by Badspot so it probably wouldn't be possible to copyright a variation of Badspots copyrighted models and graphics, since you didn't create the content but merely re-arranged it.
I don't see a © on your avatar.So stop whining.
I thought this too when I saw a drama about someone whining about a avatar theft,
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