Malcanthet is the only Demon Prince to not get the 5e treatment. But some obyriths ... Dragons that made it into Fifth Edition: Tiamat, Acererak, and Strahd von Zarovich are all old favorites.

Acererak, an archlich ... This guide details the madness mechanic in D&D 5E and how you, as a DM, can implement it into your campaign. In D&D, a lich keeps their soul in a phylactery, an item ...