Champions can no longer damage structures while invincible

Since "invincible" has multiple meanings in this game, I'm going to use it to describe something that all of these ults have in common. You can't take damage. Using these abilities in teamfights is fine, but I don't think it's fair that you can damage towers, inhibitors, etc with Kayle ult, Kindred ult, Tryndamere ult, etc. It's stupid that someone can just walk into your base, do whatever they want, and there's NOTHING you can do about it.