Crossover GATE: Tiberium Eschaton (Self-Insert)

On a certain year, a portal to another world will open, bringing war to Japan and in turn Japan would come through and take the new world for its own.

Pity the Japanese, for what this GATE will open is not a road to wealth to monopolise, but a path to witness the end of days.

On a certain year, Japan will witness an Eschaton, lit by the emerald corpseglow of a crystal sickness.