The first time you fight against Dark Emperor. If you don't know already this one is a very mean Insector. The best you can have on your team. It can knock your allies out of the board. It can electrify your Insectors from range and without any doubt it is very powerful. You would want to have all your Insectors alive at the end to have a better chance at winning this round. Start by taking out Lord Hopper followed by Bee Bee King, Muramasa Beetle and Zeus Beetle. If you managed to keep all your Insectors alive against just before facing King you should be able to win this round.