Sion's Ultimate vs Teemo Mushroom
I don't know if this is a bug or if this is as intended, but currently while Sion has his Ultimate activated he takes no damage from Teemo's mushrooms. I know when Olaf has his Ultimate activated he is only immune to the slow effect of Teemo's shroom and not the overall damage. (Just lost a aram cause sion charged our base right through 4 of my mushrooms and took no damage; only the liandry's effect was applied to him)