Looks like a texture rendering glitch, where the video card confused the terrain texture with the player's skin texture. Hmm. And he is impaled by a tree, so he became part of that tree, that's what may have caused it.
Its not really a glitch, you know when you die and your body starts to fade away? Well thats whats happening in the pic only with the dust behind him, thanks to dices wonderfull engine it cant draw the dust through the disapearing body.
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