Ultimate Mind Domination (Highest possible Spell Save DC) (5e Optimized Character Build)
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You sit on your throne of skills as your thralls bring in another one of those pesky rebels. Must you brainwash them all?!
You expect him to look up at you but instead he looks to the right at the female guard. "You stole my wife!" he screams with tear stricken eyes.
You smile and exert your will over his puny mind. He tries to resist but it's as useless as one would expect and soon he's also under your complete control. And they say you're a bad guy, now they can be together forever...
Race: Anything that has +2 on your spellcasting modifier
The highest possible permanent Spell Save DC is 28 The Character Chad is a Level 17+ character with at least one level in warlock and these magic items:
Robe of the Archmagi Rod of the Pact Keeper (only applies to your warlock spells) Ioun Stone of Mastery Tome of Leadership and Influence The Calculation +8 | Base Score +6 | Level 17+ Proficiency +1 | Ioun Stone of Mastery (Proficiency increase) +2 | Robe of the Archmagi +7 | 24 Charisma (acquired in specific Adventure Module, see below if okay with spoilers) +1 | +2 Charisma (Tome of Leadership and Influence1) +3 | Rod of the Pact Keeper
This involves the Maze Engine from Out of the Abyss (188) which says: On each of the engines turns, roll a d100 and consult the Maze Engine Effects table to determine what the engine does. 36-49 | Loud whispers emanate from the hollow interior of the engine. Each character in direct contact with the engine can increase one ability score of his or her choice by 2, to a maximum of 24
Alternatively the classic hoard of charisma tomes to get to charisma 30 and spell save DC of 31!!!
The possibilities are endless. Dominate anything, charm anything, modify memories, enslave the world with irresistible magic. Bonus points if your spells are subtle cast so no one can even tell the *suggestion* they are following came from you. Not even an outside observer. This is the ultimate tyrant