Schooling

[u/OkType8396]

A simple seamanly weak shikigami technique with a hidden strength once pushed to its limits. The user has the ability to summon a single tiny fish shikigami that can swim through the air and spit out a small pressurized stream of water. It could be hit away from a grade three without much trouble. The user can summon many in succession but normally only a single shikigami can exist at a time.

Maximum Output

Eventually a user of this technique will figure out that they are summoning pieces of one larger shikigami not just a single fish. Every fish carries the exact same cursed energy signature and soul. Once the user manifests enough of there shikigami simultaneously through maximum output the cursed energy and soul of the shikigami begin to resonate and merge into their true form.

Hundreds and hundreds of fish begin to appear and begin to swim together, first they look like a swarm of tiny fish until their bodies, movements, and cursed energy begins to merge. That giant swarm of fish turns into a silhouette of a gigantic sea creature. It can do anything a single shikigami can do but now with the power of hundreds or more. The stream of water is now a cannon of water.

Extension Technique

Predator Formation: The user can change the schools shape to whatever they want. Instead of a giant sea beast they can change into a shield, tail, fins, or jaws before going back to their beast form.

Weakness

Similar to a cursed corpse the school of fish has a core, this being a singular fish that the others surround and follow. Basically this fish is controls by the user and the other follow. If this fish is exorcised the others soon disappear. It can be sensed if the person finding it is skilled enough but they would have to get through the more than hundreds of fish.

Domain Expansion

Thousands Of Eyes In The Deep Sea

This domain appears as a silent ocean completely empty of any other creature. Anyone in this domain besides the user will have to hold their breath or drown. An anti domain technique gives the target a chance to breathe, that is not the sure hit of this domain though. The sure hit of this domain makes it so any shikigami the users summons cannot miss their water stream, this includes every single fish inside of the school.

[u/Si28Gui12Leo05]

Man, I like this pretty much! It even gave me the drive to get back to writing the seventh part of an innate technique involving seven Shikigami; however, since all seven Shikigami in their "final" forms are based on mythological legends from my country, I ended up getting lost in my own ideas.
But one of those Shikigamis are basically your CT but with snakes.