"best of fates" for a defeated hero is most certainly death, less they end up on the rack of many pointy things.
Two unique forms of torture lay before Underlords with the first being a slow corruption of the prisoner turning them to your side, while the other 'harvests' their tortured Spirit.
Subterranean Games isn't going into detail around the use of these Spirits yet as that is left to a future update. Until then we are left to dream about all those ex-heroes.
"Death is almost certainly the best of fates that can befall a hapless hero, for those that survive often end up atop one of the sadistic devices within the Torture Chamber. These agonizing instruments are happily cared for by the Succubus – for she delights in the acrid smell of burning hair and salivates at the sickly sweet scent of flame-bathed flesh."
The team describe the Torture Chamber's two uses:
"The first is a mystic flame that burns past the skin into the very fibre of a creature’s being. While this assault causes no bodily harm, even the most stalwart individual cannot endure this form of torture for long. Once the corruption has spread throughout their being these warped creatures will happily succumb to the will of their new master."
"The second form of torture ignites a blazing inferno beneath the doomed soul, the rising flames will quickly engulf the victim and render their tortured Spirit from its mortal shell."
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