For the record, the red slime is from some supplement referenced in the Arduin books called "All the World's Monsters", but I can't recall which volume. (I never had access to AtWM, any volume, so the red slime is the one of these that I am actually unfamiliar with myself.)
I have one of those All the World's Monsters packed up somewhere (some whacky critters in there!), but I believe the Red Slime might also be in one of the first three Arduin Grimoire books as well.
Phraint were totally Thri-Kreen before there were Thri-Kreen.

The Thoul I've seen in a basic book, but the Tarantella was new to me.