One name: Azir.

This guy is literally the glitchiest champ in game. I bought him just couple of minutes after he came out, and first game I've played, (i have no idea what happened) but their turret stopped attacking. It didn't work. The cooldown on ultimate did not want to show after I used it, and also the same goes for my passive. It would also have the "icon" thing on the destroyed turrets. Just a bit later, he was disabled for next 3 days or so, and once he was back I tried playing him again. The thing with cooldown on passive stayed, I got "stuck" in the wall, and couldn't move away from it, nothing worked. One more thing; when I start recalling, and as soon as I have come to the point when I'm supposed to be back in the base it'd stop. It'd just stop, the whole animation, and everything, and I'd just land back. And, once, I took teleport with him, I remember clicking to teleport on the top tower, but I actually teleported on the ward, which was located on the bottom part of river. I suppose (since I don't really use boards) that somebody else made a post like this, but I just decided to give it a go, and, maybe give you some more examples of it. And, I'd just like to point out that the "recalling" thing is constant. It's like, 1/3 or 1/5 times.