I finally exchanged the Intro with the cinematic one. The audio is not yet there, but you can watch it already.
Whenever a zone becomes unstable Cluster orbs will spawn to protect the stabilizing process, those Clusters grow in power by consuming other orbs. Their first weaponary includes nukes, which they drop from above. Yes right, from ABOVE, Cluster Orb can hover over ground. They are a nightmare to fight against, but it might be worth to finish one off.