The Biohazard Banshee originated when a laboratory researcher was exposed to a mutagenic compound during a toxic spill, fusing with residual spiritual energy from the forest to become a wailing specter bound to the contamination. Now, it eternally roams the fairways, its cries echoing as a remnant of the facility's first major breach and a harbinger of further decay.

The Biohazard Banshee exists as a semi-corporeal entity composed of concentrated toxic vapors and ectoplasmic residue, allowing it to phase through solid objects. Its wails emit ultrasonic frequencies that disrupt electronics and cause structural vibrations, and it is immune to physical damage but vulnerable to extreme temperature changes. It leaves a corrosive slime trail that glows with neon-green luminescence.

The Biohazard Banshee acts as an environmental hazard and narrative device, its wails signaling rising contamination levels and guiding players away from immediate toxic threats while adding psychological pressure to their rounds.