the glitch where you couldn't act for like half of a second has been a thing for so long. i've been playing kat and watching you for awhile now and it happens after some odd interaction with input buffering after a flash e. classic riot spaghetti code.
its not a glitch, its just when you use E with no other interaction/movement input, watch the video he doesnt move atall after e-flash he just auto attacked the tower misclick and said he was frozen till he right clicks to move to the dagger- if you press E on anyone then lose the ability to attack them or they go out of vision or you E'd to something non player unless you instantly give it another input or buffer one your chracter is frozen until you give it another input
8:40 rengar be like: "Cursed energy is negative energy, while it can enhance the body it can't regenerate it, so you multiply that negative energy against itself to create positive energy. I gave up on counter attacking and poured all my focus into the reversed curse technique. Easier said than done, I could never do that till now, but I finally grasped it on the verge of death."
5:45 ooooh so the “half second stun” is a bug! I’ve been having issues with this for SO long on both Miss Fortune and Katarina and it’s so annoying, I lost so many team fights because of that