Full name of your device  PC
Regular gameplay i think stage from 13 to 15
Description of the issue. 

In sand there is 4 counters left he removes  all and come back from sleep even when his skills are on cooldown

Rotos hp exchange i think is problem

also boss when is very low on Hp let say 5% so next hit you kill it you will do very low damage 

Second bug is also iron twins when is low hp 5% probably you do low damage unless is his turn and he get wrecked  by poison or hp burns

i dint record it second one