That bone-breaking war hammer in the background and the discarded face mask are the main clues here. They lead us to believe that this was once a red-aligned, human barbarian. Check out this image from the Time Spiral style guide:
Compare the face mask (there for filtering the toxic air of Dominaria's volcanic regions), the war hammer, and that characteristic studded leather armor. It's common for targeted spells to depict an enemy-colored creature as their target, but the look is also right on. This is an archetypal look for a red-aligned warrior in Time Spiral Block—see also cards like Torchling!
We can safely assume that this aggressive red warrior was intent on killing a blue-aligned mage, and met the business end of some transmogrification magic. That's the way the studded leather crumbles!