Was just joking lol. If I say something with strike-through like this then don't take it seriously. Quick someone write an SI fanfic where JSK girls reverse-isekaid to our world or others.
Yeah, in Karen you can't build up action points like in some others. You can attack at any point in the action bar but the damage scales with the bar, while to defend the bar must at least halfway filled. Both of those action uses up the entire bar, so if you attack you'll be left defenseless until the bar fills up, and if you defends, even if you were at full bar it'll uses up all of it. The way the game goes is you have to judge each and every Karen's attacks and decide when is the last moment you can unleash your attack, so your attack can hit that much harder, before then wait until your bar is half-full to defends before Karen finally attacks.
...I'm prolly doing a terrible job explaining it but eh, whatever. I'll download Karen now and play it. Also, "girl come down kicking open the door, then challenges player" might just be able to describe every JSK game I think, aside the talking ones.