Legendary Planeswalker — Guff

At the beginning of your end step, put a loyalty counter on another target planeswalker you control.
+1: Create a 1/1 red Wizard creature token with ": Add . Spend this mana only to cast a planeswalker spell."
−3: You draw X cards and Commodore Guff deals X damage to each opponent, where X is the number of planeswalkers you control.
Commodore Guff can be your commander.