"We were just sat there, trying to negotiate a deal with Abbeth when suddenly, without any kind of warning, the air behind and above him warped and shifted and...this....thing...came through and grabbed him. It was like a spider and a lobster had the child from Hell, and it leaned into our world from wherever it came from, hauled the crime lord up, and retreated back, taking him with it!
"Then, the air just fixed itself, and it, and Abbeth were gone.
"All in all, probably the best outcome for our meeting really."
- "Nighthawk Jimmy", Rogue
Ethereal Slayers are found in 3.0's Monster Manual II, and are monstrous hunters that lurk in the Border Ethereal, waiting for prey to come "close" in the physical plane. They then drop into that reality, grab them, and retreat back to their own universe with their prize.
Anyway, I statted these up for one of my games and thought I would share. Enjoy!