This round thing is the most annoying thing in heroic realm etc.... no matter how many times i upgrade stuff to hit harder i still cant kill this stupid HR boss

almost everyfight is in the 90%'s and i have 5 heroes left been like this for 2 days and yesterday i upped spirits over 40 levels

anyone have any advice on what i can up to help me out as i have got to 99.98 once and its driving me mad must of hit it like 2000 times in 24 hours did it non

stop for 8 hours last night too..

ty for any help i recieve appreciate it