The two sisters had worried when they caught the smell of another troll on the wind, but when they found him, there was only sadness. It was time for his Mercy Pyre.
From a distance, he seemed like any other troll, but as they watched, his path wandered without aim, striding into trees as often as around them. Sticks and stones tore through his flesh, but it knit back together at once, the gift of their kind. His blundering caused him no lasting harm. The sisters moved close enough to see his clouded eyes. His mind was gone, but his ever-healing flesh propelled him. His expression was blank and unblinking, even as he crashed over a cliff-edge and as his spilled guts were drawn back into his body.
The sisters followed until he collided with a tree and fell unconscious. They gathered up branches and tinder from the forest floor and hurried to build the pyre before he awoke. They bounded back as the flames flashed to life. The smoke began to stink of burning flesh. But there was no sound – he did not wake.