Trial boss movespeed change?

PaddyVu

I saw a video that can solo Mantikora trial boss in Craglorn and i want to give it a try but it's impossible,the boss speed has been improved by somehow and i cant outrun, boss speed is insane ( i started ESO 3 months ago so i didnt know anything about the past ) . Can someone give me the link to the patch that change boss speed?