So, in this 40 minute blind pick game, it claims yorick did 300,000+ dmg... That isnt even like possible... Another twenty minute game it said he did 100k dmg... Either yorick is broken, cause both times he was fed, or there is a glicth which reports massive dmg that didnt happen...
Fairly sure it has to do with his Ult. I could be wrong, but when the ult ghoul dies, there was 10k+ true dmg done to it, and i think that was getting reported as yorick's damage. I'm assuming the 100k+ on thresh or riven in the OP pic was because yorick used his ult on them, then they died, coming back as a zombie ghoul. Then when the zombie ghoul died, the massive true damage that was dealt to it was considered part of the thresh's/riven's damage.
