[Gameplay] Olaf Bug where taking less damage kills him instantly

I was playing an ARM game and got selected Olaf, wasn't too happy about it but oh well. As I was playing I found that I was dying way too fast. I mean a 5000 hp olaf with 200 arm/mr should not die in 1 second fast. Runes are 1 of the pictures and I will be adding pictures of death recaps as well. In every one of these fights I started at full HP before someone says you weren't or how do we know you weren't. I only captured ones that I was full hp at the start in. https://imgur.com/a/bzcPd https://imgur.com/a/nGoRm https://imgur.com/a/tpSlJ https://imgur.com/a/Jh321 https://imgur.com/a/TkdOM

Wouldn't let me add more then 1 link so I posted them here. You may have to click on them to see the whole thing.