So I ran my brother through the challenges of the Throne of Baphtar today.
He rolled up a Xurunt Frost Father and with his starting corruption managed to mutate a second arm coming off his left.
His first battle was against two brother chieftains in a duel, in which he was accompanied by a basic Xur warrior as he had elected not to make a minion to assist him with his starting exp. He suffered a mild injury, but survived and was victorious.
His tribe was then attacked by a nether swarm, despite suffering grievous injuries he successfully defeated the lesser daemons with the help of his tribespeople and his Xurunsh mount.
At this point I awarded him enough corruption to push him to his next mutation, which he managed to roll on the gifts of Khorne for, having the fortune to earn a Fist of Khorne, basically turning his bare hand into a power fist which proceeded to be very useful for him.
Next he battled an Onir, beating the mechanical dragon to death with his daemonically enhanced limb.
He was then challenged by a group of lesser chieftains, choosing to ride out and challenge them before they could stage an all out assault, promptly killing three with his daemon fist and making the others submit to his rule.
He proceeded to mutate into a psuedo-daemon, another extremely useful mutation as it made him terrifying beyond belief.
His next challenge came in the form of a Herald of Khorne, a fight that brought him close to death, cut his sword in half when he used it to parry the daemon and required him to spend infamy points to survive, but he beat the daemon down to a single wound and claimed it's sword for himself.
A giant mutant was the next to approach him, but it ultimately fled from his terrifying daemonic visage, running in fear.
Afterwards he was attacked in his sleep by three of his own people, aspiring chieftains who resented his power. One landed a good blow with a sword on him and proceeded to duel him for a few rounds before being crushed by the hand of khorne, one rolled so terribly repeatedly that I ruled that he cut off his own leg, and the third was pulped by two unarmed blows from my brother's third arm.
Finally my brother came to face his final challenge, the Brazen Beast, a possessed Xur warrior with an impressive randomly boosted statline and daemonic powers and mutations, but who was ultimately crushed by the daemon fist despite landing a strong blow after a few rounds of combat.
All in all it was a fun little session, impressed he survived the whole thing but he really got lucky with the hand of khorne and pseudo daemonhood. The hand is one of the stronger mutations a melee character can have and it doubled his damage potential, and pseudo-daemonhood made the giant, who was one of the tankier bosses, flee outright rather than fight him because I didn't think to give it fearless.
He was relying on natural healing to keep his wounds up, but his challenges were spread across 9 months, with the exact time between fights being determined by dice rolls, so he was able to survive every fight except the herald without any issue, but that fight was going to push him into critical damage before he spent infamy. He was facing getting several fingers being cut off an being stunned, which would probably have been the end for him.