Illaoi Ult on Poro King

I'm not sure what happened here. Just played a game as Illaoi and every time I ulted it just smacked the ground with no effects after. Not sure if it was removed from the game mode or a seriously bugged game. Not sure if anyone else had experiences with it but I ulted about 5 times that game and each time nothing but the hitting the ground happened. No tentacles, no damage done, and a very swift death right after.