Wrestlers rarely kill each other, check to see if any of them are holding weapons. I one time discovered that one of my hammerdwarves picked up a crucible steel warhammer (dig deeper mod, crucible steel is even harder than regular steel) off a corpse and had happily snapped one trainee's leg and another's arm.
It's also possible this is just a freak accident. Dwarves make a skill check when they attack each other while sparring. If they fail the skill check, they attack for real which can be painful or even lethal. This usually isn't the case for wrestling, since 95% of wrestling moves are non-lethal and of the ones that are most require multiple attacks (such as repeatedly strangling someone's throat), so it's very rare for even a failed champion roll to kill. However, I've personally seen wrestlers carve a path chest deep in orcs before, so they do have the capacity.
With that many corpses though, I think your champion has a weapon. Check his inventory. Also, always assign your recruits armor if you can. Order some leather from the caravans and mass produce leather armor, that'll be enough to protect your wrestlers. You only really need metal for weapon sparring.
Edit: Personally, I don't see the need for so much cross training. The only skills a hammerdwarf will use in combat are wrestling (for dodge and grappling if the enemy grabs him), hammer, and shield. Being a legendary speardwarf doesn't help him at all. Stats are calculated on raw exp gain, which is ridiculously fast to train with wrestling. Most of my wrestlers are superdwarvenly tough, agile, and strong, but they can get those stats inside of two seasons wrestling and four training armed. Let them wrestle with leather armor and a shield, then assign them chain and a silver/wooden weapon and let them train to legendary. After that, assign them steel and leave them on duty all the time. Works just fine.
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Topic: Sparring Dwarfs (Read 673 times)