you read the title. I'm homedrewing up a domain of dread and have the gimmick, so I need the darklord.

heres the gimmick. anytime anything takes a long rest in this domain, they roll on a couple of tables to see if they evolve or devolve and what new things they get! so there's dinosaurs rubbing elbows with talking animals and omicient proto-deities. 

for the darklord, I only have a vague idea about a mad scientist and a time machine. and I think it would be cool if he came there through the time machine and emo Shakespeare(dark powers) just rolled with it. and the thing that started this whole thing is remembering an episode of the twilight zone (I think) where some guy was transforming into THE FUTURE MAN! so I thought "wouldnt that be a cool thing for a domain of dread, the darklord slowly turning into something from the distant past or some impossible future" so one of the darklord's torments is slowly turning into a Green Abishai. now a couple (2) darklords have come to their domain without the mists. 1st is the god-brain of bluetspur, who was sent there through the collective brainpower of his football team when he started eating other members of the football team. the other is hazalin who came there through a portal made form his boyfriend.

so am I onto something, or am I just spitting frogs?

if you have any ideas better than mine, I'd love to hear them! 

Counter offer, going with the idea of a mad scientist lost in time; the Dread Lord is a primordial mass of an Elder Oblex, the combined remains of a genius biologist and master chronologist pair who were both attempting to travel the  timestreams to tour various ages and study monsters and people through the depredations of time. Having fused together into a sentient primordial mass, the duo has taken to their new form and home by infecting visiting creatures with trace bits of themselves and logging the weird changes that are accelerated in the night during the sleep cycles. Over time the experiments run their course and the remains are absorbed into the Oblex mass for a more "intimate" autopsy for study. As the Oblex controls both physiology and time within their realm, they are quite a formidable foe, but are sometimes weak to matters of curiosity; sometimes letting interesting adventurers who pose clever experimental ideas live long enough for the presumed test to run its course. More than one clever foe has tricked the Oblex into giving them enough rope to hang themselves, only to metaphorically swing away to safety outside the domain of dread.

Quote from Metamongoose >>

Counter offer, going with the idea of a mad scientist lost in time; the Dread Lord is a primordial mass of an Elder Oblex, the combined remains of a genius biologist and master chronologist pair who were both attempting to travel the  timestreams to tour various ages and study monsters and people through the depredations of time. Having fused together into a sentient primordial mass, the duo has taken to their new form and home by infecting visiting creatures with trace bits of themselves and logging the weird changes that are accelerated in the night during the sleep cycles. Over time the experiments run their course and the remains are absorbed into the Oblex mass for a more "intimate" autopsy for study. As the Oblex controls both physiology and time within their realm, they are quite a formidable foe, but are sometimes weak to matters of curiosity; sometimes letting interesting adventurers who pose clever experimental ideas live long enough for the presumed test to run its course. More than one clever foe has tricked the Oblex into giving them enough rope to hang themselves, only to metaphorically swing away to safety outside the domain of dread.

ohhhhh that's an idea. what if it was the biologist and chonologist, fused together in a temprol accident into some kind of flesh blob, and are evolving into an Echo of Demogorgon?

Sure? The concept is kinda flexible.