Bio Hazard Battle (known as Crying - Aseimei Sensou (クライング 亜生命戦争) in Japan and Crying (크라잉) in Korea) is scrolling shoot'em up developed by Sega. It was published by Samsung in Korea and by Sega in North America, Europe and Australia. The game was also released in the arcades via the Mega Play.

The planet Avaron was plunged into deep biological war known as G-Biowar I. A retrovirus was synthesized in order to defeat the enemy, but the plan backfires: the planet is rendered nearly inhospitable to mankind, and the only survivors of the virus are sent to space in the O.P. Odysseus to await a time when the new species of creatures that survive or thrive on the virus pose little enough a threat to set up a new colony. Eventually, collected data shows that conditions on Avaron are now hostile but livable, and thus the Odysseus deploys special craft that are both machine and living being, known as Bioships, to scout the areas of the planet labelled least hostile and find a new home for the survivors.

There are four different Bioships to choose from. Each ship has forward shot and a satellite which fires a second weapon. By holding down the non-auto fire button, you can charge a plasma shot. The plasma shot of each ship is individual. The second weapon can be altered by collecting orbs. There are orbs in four different colours. Some get different weapons for the same colour. For example, the red orb will give some ships bouncing shots, while the others get a homing attack. Each weapon can be powered up by collecting the corresponding orb several times.

The game can be played in 2-play coop, but players have to choose different Bioships.