Insanity Magic (5e Subclass)
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This is a subclass of the sorcerer class. You may have been a normal commoner or even a great noble but a great and terrible power has now grasped you, the power of madness. Something in your mind has unhinged, and in an absolute fluke this has unlocked a hidden magic that lies within the minds and hearts of all beings. Your thoughts run together, you twitch and gasp, perhaps laughing or crying at random. However no one dare snicker at you for the magic your madness has unlocked is as fiercely powerful as it is uncontrollable.
Upon taking this subclass at 1st level, your mind has erupted into a cacophony of thoughts and senses, and being as it is already in this state it resists effects that would render it this way. You are now resistant to psychic damage.
At 1st level, your mind can convince your body that it is much stronger than it actually is. After finishing a long rest you gain temporary hit points equal to your charisma modifier. Additionally, when you take damage you may choose to halve it as a reaction. You may do so again after finishing a long rest.
Starting at 6th level, your mind recoils violently against those who attempt to enter it without permission. Anyone who attempts to read your thoughts with a spell must pass a wisdom save against your sorcerer spell save DC. If they pass the spell functions as normal but if they fail they take your charisma modifier worth of d4's in psychic damage (minimum of 1d4) as their spell does not reveal your thoughts but bombards the caster with shrieks of anguish and laughter from the chaotic depths of your mind.
Your mind is now so deep in insanity that other mental states have a problem controlling you. Starting at 14th level, you gain advantage on saving throws against being frightened or charmed and you cannot be magically put to sleep. You also add your charisma modifier to the damage of any spell that deals psychic or force damage.
All Consuming Madness
At 18th level, you can use your insanity to free the minds of others from negative effects and steal positive ones from your enemies. The number of times you can do this is equal to your Charisma modifier. As an action, you can target a creature within 5ft that has a magic effect currently affecting it, such as the sleep or haste spell. If the creature is willing you may take the effect as though you were the original target. You gain all effects of the spell with the exception of the spell's duration which still counts down as though it was on the original creature. If the target is unwilling they must make a wisdom save equaling your sorcerer save DC or the effect is forcibly taken from them. Even if the caster of the spell ends the spell early you gain the taken effect for at least until the end of your next turn as your chaotic energies keep the spell alive.