WN/Beast Fusion

Medical Skill Beast Fusion (獣身化), is a skill that was developed by the team responsible for the analysis of Demon Beast DNA.

This skill fuses the Demon Beast and it's handler together. Letting a human attain the power of a Demon Beast (a forbidden power). The reason it was called a forbidden skill, was because it became impossible for the individual who activated it to cancel the effects.

The drug used for the skill had to be surgically removed in a facility with the appropriate tools. Through the fusion of the handler and his partner, a warrior that surpassed the original concept/individuals would be born.

The drug was distributed and kept on hand, so it was possible to activate whenever necessary. But, usage is prohibited without the Secret Command from the corps leader, Gradim.

There was other reasons why it was "secret." Which were:
 * Risk of death: 10%
 * Risk of compatibility failure and completely turning into a Demon Beast: 20%
 * Risk of losing control (applies for both Beastman and Demon Beast): 30%
 * Risk of side effects resulting from the fusion: 20%

There were many underlying problems. There is only a 20% chance for the "complete" success of the fusion.

Empire's Invasion Arc
Having witnessed the numbers and rank of the demons which Rimuru Tempest summons to battle the Empire's forces Beast King Gradim issued the Secret Command giving his subordinates permission to use the Medical Skill Beast Fusion.

Like Gradim, there were corps members who successfully fused and completed the process. These members consequently attained new powers and became stronger. These perfectly compatible individuals made up less than 1% among the entire corps. They were called Chimera Knights and were the aides of Beast King Gradim.

The order that Gradim issued, was akin to a death sentence for the Beast Corps troops. If there were unable to attain power now, they will simply end up as fodder for the demons. It was a cold, but pragmatic order. And the troops swiftly followed it.

They had prior knowledge to the risks of using Medical Skill Beast Fusion and knew of the high mortality rate. But because they had absolute faith in Beast King Gradim, they followed the order without hesitation.

The Result
Of the 30,000 members of the Demon Beast squad that used Medical Skill Beast Fusion:
 * 7,700 turned into berserk Demon Beasts.
 * 5,800 into complete Demon Beasts.
 * 4,500 turned into berserk Beastman.
 * 7,400 into Demon Beast-man soldiers.
 * 550 turned into Chimera Knights.

It resulted in a fairly large loss in numbers.


 * Only 13,750 of 30,000 were still sane and combat-ready after using Medical Skill Beast Fusion.

Effects
The Chimera Knights obtained the Unique skill Bodily Manipulation.