"They thought they could hide a war crime beneath a bank vault and call it a corporate asset. D.K.-09 is about to learn that the GDF doesn't negotiate with monsters—whether they wear body armor or crawl out of their test tubes. Move out. We're burning this rat hole to the ground."

When a brazen daytime heist at the city's central bank shatters the peace, the Global Defense Force (GDF) uncovers a terrifying reality: the robbery was merely a diversion for a subterranean military syndicate known as D.K.-09. As elite strike team leaders Tereshkova and Neil mobilize their operatives—alongside a mysterious time-displaced veteran named Talon—the mission spirals into a desperate race against time.

Dropping deep into D.K.-09's classified, multi-tiered underground fortress, the GTF must battle through brutal rocket-wielding juggernauts, ruthless flamethrower squads, stealth assassins, and rogue scientist-researchers. But as they push deeper past shattered bulkheads and blood-slicked corridors, it becomes chillingly clear that something far worse than human soldiers has broken out of the lower labs—something massive, lethal, and hunting in the dark.

With the facility's self-destruct countdown ticking down and the entire mountain base collapsing around them, the strike team must fight their way through the chaos, punch through the central vault, and secure surface extraction before they are buried alive with the syndicate's darkest secrets.

(Because the game itself was a arena shooter for the Dreamcast console in 2001 (Arcades in 1999), the lore of the series is extremely obscure, so I was able to piece together something from what I was able to dig up, I hope this proves to be a good experience, given how limited the source material can be)