With every damage multiplier and OHK not working and being banned especially during raids. This is a workaround and it works for League Raids and Solo Raids.
Basically you need to have heroes like Primal Swamp Thing or Unbreakable Cyborg who can resurrect one more time after death. Before entering a raid, make sure you turn on OHK and Anti-Ban. Once in battle, don’t do anything and let the enemy hit you. As the heroes mentioned return after being knocked out, they inflict damage onto the enemy without actually killing him. The enemy will be left with only 1HP but don’t finish the job and kill. Instead, let all your heroes die.
The next time you enter the raid, you can turn off OHK. Use any hero of your liking and just deliver one hit. This will ensure you clear the raid without getting any suspicious activity.
This can be used in Arena too. The workaround is by letting 2 of your heroes get knocked out and allow your last hero to knock out the opponents. This will also negate the suspicious activity.
Hope this works!