Born in a small border town that was raped, looted and pillaged by an Orc warband some years ago. He was the result of one such rape, and grew up shunned and feared and bullied on the streets of the town which had become heavily militarised and secured by forces from the local human nobility. He was hardly the only result of war-crimes, and he hung out with several other half-orc friends as a small, untrusted, community within the town.

But he and his Half-Orc friends had some hero worship of the troops that had driven the Orc warband back and kept them safe in the years since, so he (and several of his friends) enlisted in the noble's army. But he quickly found that he and his other half-breed comrades were used as “cannon fodder”, rather than treated as skilled warriors. Tunn started to learn a little field medicine (something with which he discovered he had some talent), trying to keep his friends alive, but he lost many along the way.

Recently, he was part of a formation sent to clear out a “terrorist hideout”. Whilst the main force held a perimeter around the Orcish camp, he and his friends were sent in as part of the frontal assault as a distraction from a human stealth attack. It was a surprisingly easy attack, and when Tunn made it inside, it saw why. It wasn't a terrorist cell — this was just a camp of starving, frail, children and elderly Orcs who were almost defenceless. And many of them had been slaughtered in cold blood (if not actual joy) by the human assassins. Even worse was the fact that some of his friends and comrades were following orders and killing the weakest of this poor tribe that were clearly unaggressive.

Tunn looked at the scene there and then and took off into the night to forge his own path. He knew that his absence might be noticed eventually, but he trusted that the human officers wouldn't really care about one less half-breed, so he should be able to still mingle with the rank-and-file at any point without trouble (if he wanted to).