I've seen some bosses that cannot jump, but instead of that, have good anti-air attacks to punish jumps or attacks with insane vertical range to suffice that. And they really don't need to jump at all because of this.
Hope this isn't going to go too offtopic :p
But, the point is, he can't do anything in air or against air.
The only way he can counter airborne opponents in using his super, which hits anything in his near.
He used that same super in the yt video you posted.
Kamui is only capable of using 3 stand/crouch normals
3 variants of casting a lightning, shoot a straight projectile and the most abused move he uses is the teleport which grabs his opponent.
The lightnings hit straight from top to bottom, the distance depends on W/M/H.
His projectile flies slowly across the screen horizontally, causing multiple hits.
The teleport+grab thing makes him dash across half a screen and grab his opponent if he connects.
And in BBBR, you can almost instant grab an opponent who stands up from the ground.
That's what makes his cheap in an actual fight.
To win against Kamui, you can easily beat his with a projectile spamming character or go aerial like in the video shown.
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