Mordenkainen's Tome of Foes presented several creatures that would be classified in Monvesia as
thoughtforms. This includes: natives of the astral plane (allip, astral dreadnaught, berbalang), beings created to serve in the Mortal Realm (eidolon), and even beings born from the
Taint (gray render, oblex, sorrowsworn). The latter are classified as
taintspawn, and each plays a unique role in the overall mythos of the Taint.
In their original forms, the taintspawn are monstrosities and oozes; but in Monvesia, they are physical manifestations of of thought and will that have been channeled though the taint itself. Not all of these creatures are necessarily evil, however.
For complete statistics of these creatures, check out Mordenkainen's Tome of Foes.
