High Republic · Prequel
The small lives as will.
Darth Plagueis the Wise
Sidious’s Master. Canon shows a Muun in the cave behind Qimir and lets Palpatine tell a tragedy in an opera house. The rest is implication.
Dark Lord of the Sith. Muun · Mygeeto. Deceased.
Death
Murdered by his apprentice in his sleep — the story Palpatine tells at the opera. Canon does not stage the killing.