All of K-Style. These are techniques that should technically violate the game's rules (as they are exploits of the animation system), and yet everyone uses them. These techniques are ALWAYS preformed with a block tossed in. What this means is if you try to attack with a sword, your sword will bounce off harmlessly (IF you can hit) and stun you for a moment while you get torn up, and your bullets will be blocked by the sword. Should you be hit by a single sword swipe, you will die to a K-Styler due the fact a single slash will stun you for JUST enough time for either the second hit, or a pair of ridiculously fast shotgun hits (mentioned above) will hit you and kill you instantly. That, and every K-Styler has either a) practised for hours at these combinations b) uses a trainer, meaning it's all done so fast it's a blur. It turns a game that SHOULD be a Matrix style shooting game with lots of sword play tossed in into a "use K-Style techniques or die" game.
This attitude just bugs me. K-Style isn't superior, yet everyone acts like it is. How many K-Stylers do you see using revolvers or pistols? None, because they can't aim. Their "pro moves" are easy as hell to blast, even with the block, and they're too distracted doing all these complicated moves to aim and dodge like a normal person.
Well, revolvers are popular among K-Style users who do realize what aiming is, but outside of those few, yeah, rifles and pistols are completely ignored. The only thing that's truly gamebreaking about K-Style is the Reload Shot due to it making it completely unnecessary to aim or reload. Outside of that, K-Style's main weakness is that its pretty much useless at long range. Just fight from halfway across the map and ignore their complaining about how you're a "sprayer noob."
last time I played(quite a while ago, before fashion items were even in the game, so things have probably changed) a friend and I developed a very simple trick for taking out anyone who wasn't well practiced, it was as simple as turn(they always seemed to favor skipping to the left to hit you from behind) block(they dash back, then forward then hit) smash(if they didn't cheat their way out of the stun from being blocked) shotgun, back-roll, repeat(even worked on guys who were pretty good at it, just took a while, turtle until they make a mistake / run off of a cliff by accident)
K-style isn't perfect, even though every k-styler seems to think it is. All styles have weaknesses. K-stylers are too predictable, d-stylers are too fragile ( and the worst ones are predictable too ) and e-stylers are too slow ( and fragile ).