School of Memory

This subclass focuses on the Encode thoughts cantrip as well as relies heavily on spells like detect thoughts and modify memory in order to best manipulate the minds of others. The class is a mix between the schools of enchantment and school of illusion and provides a lot of good roleplay potential as well as some interesting combat situations. This is my first homebrew ever so it is likely a little rough.

Strengthened Strands

At 2nd level, you have learned to enhance the uses of your thought strands. The duration of the strands created from your encoded thoughts cantrip increases to 16 hours and can be stored inside your spellbook. This time strand lasts increases to 24 hours at 6th level and the strands last indefinitely at 10th level.

Additionally, the strands you create are the raw memories, thoughts, and ideas so you and all other creatures affected by your abilities of the class understand them in their native language regardless of what language the thought is in. Starting at 6th level, you are able to make the thought strand be heard in any voice or language that you have heard.

Thought Encoder

Starting at 2nd level, you learn how to insert thoughts into other people's minds. If you have a thought strand you are able to send it into the mind of a willing target within 30 feet of you. That creature gains information of the memory, idea, or message in that strand. You may also attempt to send the strand into the mind of an unwilling target within 30 feet of you. The creature must make a Wisdom saving throw against your spell save DC. If you are fighting the creature, it has advantage on the saving throw. If they succeed, the strand does not infiltrate their mind and they are aware that you attempted to modify their memory. If the target fails the save, your strand intercepts their mind. You can choose if they believe the memory or idea is theirs (this does not mean the target will act on it just that the target believes that they thought of the idea, as you become a more powerful Wizard the target may be more inclined to act on the thought but this is up to the DM) or if they just receive the information from the strand. Doing this destroys the thought strand used.

If the target you choose has an Intelligence of 3 or lower or doesn’t have a mind to infiltrate (such as an animated object), the target is unaffected.

Memory Theft

Starting at 6th level, you learn to steal the memory of others and yourself. When you cast your Encode thoughts cantrip you are able to erase the memory from your mind completely. If you cast this spell while concentrating on a spell or an ability that allows you to read or manipulate the thoughts of others such as Detect Thoughts or Modify Memory you can pull a memory of theirs from their mind completely.

If you use this ability on a creature that is able to cast spells, you can remove the knowledge of a spell they know from their mind. If the creature attempts to cast a spell forgotten this way, they must succeed an Intelligence saving throw. If the spellcaster succeeds, they cast the spell normally. If they fail the save, they attempt to cast the spell but nothing happens. This effect lasts until the spellcaster takes a long rest or has its memory of the spell restored. 

When you steal a wizard spell of 1st level or higher this way, you can add it to your spellbook if it is of a level for which you have spell slots and if you can spare the time to decipher and copy it. For each level of the spell, the process takes 1 hour and costs 20 gp. This process goes much faster than the normal spell copying method due to having the original caster’s knowledge of the spell. Doing this destroys the thought strand in the process.

Thought Projection

Beginning at 10th level, you learn to turn thought stands into illusions. While holding a thought strand you are able to turn it into a projection of the idea. You can choose to have the illusion take the form of yourself or the creature that the thought strand is from. The image appears at a spot that you can see within 120 feet of you and lasts for 10 minutes. The illusion performs the action or spouts the information that was encoded into the memory strand. Physical interaction with the image reveals it to be an illusion because things can pass through it. A creature that uses its action to examine the image can determine that it is an illusion with a successful Intelligence (Investigation) check against your spell save DC. 

Using this ability destroys the thought strand in the process.

Mind Wipe

At 14th level, you learn to steal every memory a person has. When you use your Encode thoughts feature, you may attempt to steal a creature's mind from them if you are concentrating on a spell or ability that allows you to read their mind. To fully steal the target’s memory you must spend one minute casting encode thoughts on the target and be able to be reading their thoughts the whole time. The attempt fails if you become unable to read the target's mind or if you go a round without casting encode thoughts on the target.

If the attempt fails, you gain a strand with all of the information gathered, but the target does not lose any of its memory. If the attempt succeeds, the defending creature becomes a husk of its former self as its intelligence becomes 3, and relies on instincts alone to survive. The strand you create from this is very large and takes the form of a large spectral spool of yarn. Regardless of the result of the attempt, you suffer one level of exhaustion and are unable to use your encode thoughts cantrip, your Thought Encoder feature, or your Thought Projection feature for 1d4+1 days.

You are unable to insert this full strand into another creature’s memory with your Thought Encoder feat unless you break the strand up. Alternatively, you are able to insert this strand into a creature with Intelligence 3 or lower or something like a construct, simulacrum, or magic weapon turning it into a sentient weapon. Because the new body or object has the memories of the old target it now shares largely the same personality of the owner of the memories.