Good hunter, beware the Zindaur Sun Priests.
These radiant clerics worship the sun deity Zindaur and pack a deadly surprise. When killed, a Zindaur Sun Priest transforms into a vicious T-Rex for one final stand!
The idea of a cleric morphing into their deity's sacred form when slain felt very fitting thematically.
P.S. For more primal monsters, check out "Echoes of Extinction" on my Patreon!
(Dungeons & Dragons 5e Monster)