DMM (Dungeon Master's Master)

Start saying a chant saying random stuff repeated for a minute with a star in a circle appearing under you until it creates a beam opening up the sky striking a black lightning strike on each point of the star and then on every point at the same time at the very end.

The DM can't affect you unless you accept the affect, and you can reroll anything as many times as you want. Basically, free will and you can add any homebrew characteristic, spell, attribute, item, or anything in general to your character if you have enough slots/space. You can also use this as a wish spell for anything and you practically become the DM.