Ioneion, System Control Flow

Ioneion, System Control Flow is the final boss of the Headlong mission in Destiny 2: Lightfall, set in Neomuna. Some guides spell it Ioneon. The fight takes place in a large room at the end of the VexNet, where a rotating trap has to be avoided throughout. Waves of Vex enemies come first, and the boss appears once they are cleared. The boss is described as large but slow. Completing the mission grants a 500 Neomuna Rank boost and 2,500 Glimmer. The chest that opens as you leave the VexNet may contain gear, an Upgrade Module, and more Glimmer.