There are 2 kinds of cheating
1. Exploit
Oversize Donated Troop
Oversize Garrison Troop in War base
Reusable Troop card
2. Hack
Unlimited Crown
BHG do nothing for both, and you can see there are numbers of account which appeared suddenly but with maxed defense and whiten wall
Especial when you facing player from south east countries (Vi***** )