important information and explanation

anti-magic swords:

( all swords are within the anti-magic demon because the orginal grimoire is merged with him,he can unlockthe swords with the help of the system )

Demon Slayer(large sword/can cut,nullify,bounce back magic/can fly on it)

The Demon-Dweller sword(smaller/,same abilities but can absorb magic(can absorb emitter types of quirks, like fire/ice/wind)and use anti-magic slash)

damon Destroyer sword(it is able to destroy the causal relationship between spells and the natural world through an ability called Causality Break. By doing this, the sword can retroactively change the flow of time and nullify Reincarnation Magic

Demon Slasher  katana (yami sword can release anti-magic slash that has the special ability to only cut what the wilder desires(like when asta saved yami from the king of devils in the manga:Demon-Slasher—Infinite Slash Equinox )

ki sensing:the ability to sense life

(zetten)

By precisely manipulating their ki, the user builds up magic power within their own body and concentrates it into their limb. Subsequently, the user swiftly performs a physical motion, such as a punch or a kick, and explosively releases the magic power, generating a focused blast of energy from their limb. This energy's form depends on the physical motion; for example, a hand swing will generate a flying slash that is capable of slicing targets from a distance.

Alternatively, the built up magic power can be equally split among multiple attacks, depending on the user's style of fighting.However, Zetten's strength is determined by the amount of magic and the speed of the action, so the individual attacks will be weaker.

Zetten can be utilized alongside other spells, increasing their power, and can be replicated with anti-magic /(from 20× or 100× booster )

transformations:

1-(half devil mode)

demon form is a sight to behold: Red-eyed, half black hair, horn sprouting from one side of his head, two elongated canines, and a black wing sprouting from his back all combine to create the perfect demonic

2-(rage mode)

overcome by malice while in this form, the black Anti Magic covering his body will become more fiery in appearance, cover more of his face, and will transform his right hand and foot into claws. Two additional horns will also form on his head, a smaller black wing will sprout from his left shoulder, and an arrow-tipped tail will appear on him

3-(devil union mode)

The host draws on the full power of their devil and assimilates the devil into their body, enabling them to contain and control the power of the devil and dramatically increasing their own magic power and capabilities. The host takes on physical traits of their devil, such as horns, a tail, and slit pupils, as well as being garbed in their devil's power.

Additionally, the host can integrate the devil's characteristics into their magic. For example, Gimodelo's "Pack" enables the host to create multiple clones of themselves.If the host is contracted to more than one devil, then they are able to unite with more than one devil at a time, resulting in a more powerful unite mode.

If the contract is one between master and servant, the host can easily use Unite due to having full command over their devil and, while united, the host's mind is dominant. In a contract of equals, however, the process is more difficult, requiring the host and devil to work together and synchronize their thoughts.While united, their minds and personalities overlap, until they perfect the union by better understanding each other and sharing the same motivation, at which point they truly merge.

4-(true devil union mode)

when the host and demon truly understand each other they reach true union mode that gives explosive power and additional horns