The premise is that you have to look at it from an Oriental perspective.
Planet fragments entrained unwilling souls to reach the earth are like ghosts in Eastern culture. The ghost can't be destroyed by physical attack, because it doesn't possess the entity itself. The Zeus cannon proposed by the general is an energy attack method. Since the energy attack is an energy wave, it can be destroyed temporarily, but the ghost that absorbs energy will only become stronger.
The dead souls in the film can only use the lives that survived hardships, that is, the eight souls that the doctors in the film are struggling to pursue. Finally, the soul of the male protagonist was used as a medium to amplify the power of the eighth soul, and to dissolve the hostility of the wrong soul in a super-severe way, making it disperse into stars in the sky.
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