There is no psionic monster beginning with R, so I am going to go with something a little creative today: the Greater Kraken. You gotta admit, the Kraken is an epic monster. Its appearance in any number of major motion pictures attests to that.
But there are elements of the Kraken that really intrigue me, evoking the possibility of something greater than merely "extra-giant squid":
-- INT: Genius+
--"It is said that at one time these monsters were smaller, lived in shallow coast waters, and had human worshippers who served them and brought them sacrifices."
--"It is rumored that some kraken maintain complexes of caverns wherein they keep and breed human slaves to serve and feed them."
Taken in totality, Genius intelligence, human worshippers and human slaves all imply one thing: PSIONICS.
Imagine one of these things slowly rising up out of the water, head first, until its eyes are visible, hovering above the still, dark, water...
Red, glowing, pulsing eyes, entrancing you, drawing your closer...
You stare into its eyes, while its mind works its tentacles into yours, taking over your thoughts, strangling your will to fight...
The Role of Kraken in the Underdark
These Greater Kraken are another race of tentacled slavers vying for Underdark supremacy, neutral evil in alignment.
Like the other tentacled slavers of the Underdark -- the Aboleth and the Mind Flayers -- they use their slaves as a proxy army, to wipe away their enemies (especially the hated Duergar, who can resist their psionic powers).
When not fighting to expand their kingdom, the human slaves worship the ego-maniacal Kraken, and build up magnificent temples and monuments to the glory of their Kraken overlords. Kraken slaves can also be found digging, expanding and connecting the underground seas which are the Krakens' domain.
Their power of Molecular Rearrangement is utilized to make their underdark kingdom an incredible sight to see - and full of uncountable riches - as statuary and other objects made of precious metals abound.
Their willing worshippers are often rewarded either with weapons transformed into mithral steel or adamantium (the material base for +4 and +5 weapons).
attacks: 6-8 tentacles (2 barbed) + bite -- 2-8 (2-12) + 5-20
Psionic Ability: 236-265
attacks: Mind Thrust, Ego Whip, Id Insinuation, Psychic Crush
defenses: Mind Blank, Thought Shield, Mental Barrier, Intellect Fortress
Animal Telepathy, Detection of Good/Evil, Mass Domination, Molecular Rearrangement
control temperature, 40' rad.
3x per day:
animal (fish) summoning III
1x per day: