Kabal is a threat from almost anywhere on screen, but is especially difficult to deal with from about 2/3rd and closer, where his safe downward air buzzsaw becomes a threat. It allows him to condition the opponent not to anti-air. He can even whiff an air normal and still use the buzzsaw. Once conditioned, Kabal starts getting a lot of free jk and j2 pressure and even empty jumps into pressure. Speaking of his j2, it's similar to Catwoman's j2; not as good, but similar. He has excellent horizontal reach, making it difficult to anti-air even without buzzsaw conditioning.
His staggers are very good, and in this variation he gets 50/50s off of several of them. The overhead options are all totally safe, with f224’s overhead only being -2, forcing the opponent to respect your 7-frame d1 afterwards, limiting them to poke punishes.
His normals have nice reach and hitboxes, with a lot of solid, fast mids. He has a lot of weird block-stun and animations on his strings, which allows him stagger with strings that shouldn’t really be staggerable.
His back throw keeps the opponent in range of all his staggers, allowing him to keep up his pressure. Unfortunately, his front throw sends the opponent full screen, which is only useful in a few matchups.
He’s got a 9-frame mid that leads into a 50/50, where the overhead is safe (-5). This, combined with his restand (db3), essentially makes him a vortex character. Every time he lands a combo, you’ve got to respect that 9-frame f4, which opens you up to throws and other strings.
His f3 has massive range, is +6 on block, and can be canceled into his restand for over 18% damage (just f3~db3).
He can cancel his pressure into AMP bf1 to remain -1 on block or get a full kombo on hit. The buzzsaw is a high, though, so it can be risky.
Finally, his d1 and d4 are both exceptional. He can cancel either into db4(?), his mid-hitting hook swing special, to keep the opponent from counter-poking.
Oh, and none of his major tools have any gaps.
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@Trini_Bwoi said, you can tell he was a "mathematically-designed" character. His tools just compliment eat other very nicely, resulting in a ton of synergy.
One final note is that Kabal almost doesn't need offensive meter. He can use it to make straight buzzsaw -1 and kombo, or to make his downward buzzsaw safer, or to tack on a little extra damage to his hook swing special, but those are all just little bonuses that don't really affect his overall viability.