This week our group engaged a group of devil worshiping centaurs and a Bone Devil they had summoned who had escaped us a couple weeks ago.

My warlock kept out of range of most of them by dint of riding a special Figurine of Power that is an Arisen Nightmare (a Celestial Nightmare, just replace Fire with Radiant, give it wings and take away the Ethereal Step ability), most of our group had Fly on them and the Bone Devil went down quick because of a Holy Avenger crit from the paladin.

After that though, with civilians of the herd starting to sacrifice themselves to the blood pond, the paladin (Of Redemption, afraid of losing his oath) and the rogue (Not wanting to kill kids) tried to talk things down. The dark priestess was hearing none of it and just wanted us dead.

Pretty soon four adults and a child had unalived themselves into the now black and bubbling pool, the priestess was dead and growing into some sort of gnarly tree, and our barbarian half orc was dead. The rest of the group started to flee, but my Warlock had a couple remaining desperate attempts in that I had a couple of scrolls of Guiding Bolt in my pocket.

With a prayer to the Sun God and the Nature Goddess, my DM allowed me the first try and after a religion check, a damage roll and a D100, a bit of the pond purified, but that didn't last long and top of the next round, a visage of the Archdevil of the Fourth Circle came up, anointed a new priestess, inflicted fear on our bard and my steed (They were the only others in range and I passed the saving throw) and slumped back into the pond.

My steed, frightened, used it's next action to dash the fuck out and the Bard did the same. The steed carried me a good distance before passing his fear check to break it, and we decided we had to do something about it, even as the rest of the group was hauling ass to both get away and get the Barbarian revived.

The steed swiftly carried me back to the spot we had just been and joined me in prayer, adding the God of Protection and Goddess of Justice on his end, and with another religion check, a damage roll and a D100, the pond was wholly purified, if only for a moment, before evaporating, leaving behind a red stained crater, and a momentary visage of a devil who's summoning we'd apparently interrupted and who got a good look at me before fading back to the Hells

Blood Pond image clipped from - https://www.deviantart.com/skvor/art/Dark-Pond-635218185 Trident Throw clipped from video "Myth's Bad End"- https://www.youtube.com/watch?v=euPfAilSpuU