Thread by @ghirapurigears

Mordenkainen had to be a planeswalker. He's one of the most famous characters in all of d&d, being the PC of Gary Gygax himself, and the character who has been continuously active and relevant in the game the longest, since 1972

Mordenkainen is an archmage of Oerth, though he is well known on Toril (the realms), and he leads a group of wizards known as the Circle of 8, with folks like Bigby, Otiluke, Otto, Drawmij, and Tenser, all of whom are famous in their own right

I can't imagine having Mordenkainen and not having Elminster, though

Also, see that middle power? One of his most famous spells is Mordenkainen's faithful hound, which summons an invisible watchdog to make an alarm if something sneaks up on you, and to attack as needed. Very cool to see

Not sure about his auto ultimate if you have doubling season, though.