Knowing from where the enemy was coming, Krune asked Light Spirit to help cover his Flying Shields as well. Because the shields were made of Tribulation Ore, it was easier to use Tribulation Lightning on them. Light Spirit did as Krune asked, and with that, the shields were also hidden from the enemy's Divine Sense.
Krune had only one plan, get rid of at least one of the enemies before the rest came over. Even though they could use the teleport formation, there is no way to say if the assassins will be able to find a way to enter the inner core region. So it was best to eliminate part of the danger straight away.
Krune had told the others what he was about to do, but Hulibe Acrol was against it at first. Acrol and his friends still could fight at the Divine Soul Realm level once more, so he wanted to be the one to make the attack. But even though Krune didn't know why Hulibe could fight those guys, he decided to refuse his idea.