Resident Evil Gaiden

Resident Evil Gaiden (Biohazard: Side Story in Japan) is a Resident Evil game featured on the Game Boy Color handheld platform. The game was developed by now defunct European company, M4 Ltd, rather than Capcom. The game's events are not acknowledged anywhere else in the series. Shinji Mikami was involved in the game's development.

Story
After the events in Raccoon City, an underground anti-Umbrella organization formed to stop Umbrella's evil deeds. A new Bio-Organic Weapon (B.O.W) developed by Umbrella is rumoured to be aboard the cruise ship Starlight, so Leon S. Kennedy is sent to investigate. Shortly after he boards the ship, HQ loses contact with him and Barry Burton is called to carry over Leon's mission. Upon his arrival, Barry finds out that an outbreak similar to the one in Raccoon City has happened on the ship.

Shortly after, Barry goes to the ship's Security Room and sees a scared girl through a camera. Using an intercom device Barry talks to her, finding out her name is Lucia, and asks her about the ship's events. They barely could cross words, however, as the B.O.W was ramming the door of Lucia's room, and she desperately asks Barry for help. After asking her location, Barry rushes to the scene and with a few shots sends the B.O.W away.

Having Lucia with him, Barry continues to search for Leon, but upon approaching his location, Lucia says that she "feels" the B.O.W is near. Surprised, Barry asked about her odd ability, but the B.O.W reappears and abducts Lucia, leaving Barry alone. Barry then finds Leon alive, and then they team up to find Lucia. They find her on the ship's deck and Leon and Barry fend off the B.O.W using their guns, giving them enough time to flee.

Lucia reveals her background as an orphan child that was picked on by the other kids because she was "different". She couldn't stand that situation anymore, so her adoptive family sent her to Europe in the Starlight.

Shortly after, the B.O.W begins to harm the ship, causing an internal explosion, so Leon and Lucia are forced to activate the sprinkler system while Barry takes care of a "personal matter." That matter is revealed when Lucia and Leon see him through the security cameras arranging a deal with someone to give them Lucia. Leon then goes and confronts Barry, but Barry holds his gun to Leon and takes Lucia away with him, to an Umbrella submarine. Leon has a shoot-out with some Umbrella soldiers, but they flee quickly.

Left for dead, Leon hears more explosions coming from the machine room, and in the fear that the ship is sinking, he goes there to fix it and try to buy some time, he finds the B.O.W. After a showdown with it, Leon wins, but he is resigned to his death in a ship that is just about to sink.

Meanwhile in the submarine, the Captain reveals that Umbrella wanted Lucia all along because she was the real B.O.W, the other one being a decoy. Barry then mentions that the B.O.W. supposedly has green blood so the Captain explains that the B.O.W. is a parasite using Lucia as a host. Barry then betrays the Captain, saying that his original intention was to find a means of escape from the Starlight; then he forces the Captain and his team of surgeons to extract the parasite B.O.W from Lucia's body. Shortly after they do so, the creature moves on its own and attacks the captain, turning him into a zombie. Barry then kills him but discovers another outbreak in the submarine caused by the B.O.W from the Starlight, which was in the control room roaming free. After Barry and Lucia find their way to the control room and guide the submarine back to the Starlight, the B.O.W goes back to the ship. After arriving to the control room they find Leon, who escaped from the sinking ship. After the trio reunites and are just about to escape the ship, the B.O.W makes his final appearance. After the hard fight, they run from the Starlight and watch the ship sink. Leon makes the final report to HQ, saying that the mission is accomplished, but then a scene is shown where there appears to be a small cut on Leon's neck dripping bright green blood...

Characters

 * Leon S. Kennedy: Ex-Raccoon Police Department cop, Leon is now enlisted in the anti-Umbrella group. He is sent in first to investigate the mysterious ocean liner Starlight. HQ Lost contact with him shortly after he arrived.
 * Barry Burton: Former officer of S.T.A.R.S., Barry has been sent to the Starlight to find out why HQ lost contact with Leon, and to find evidence about a new B.O.W. developed by Umbrella Corporation.
 * Lucia: A mysterious young girl found on the ship, she has the newly developed Umbrella B.O.W. inside her body.
 * HQ: Through the game, a radio operative from HQ will be in permanent contact with you.
 * Captain: The Captain of a submarine sent by Umbrella to retrieve Lucia.
 * B.O.W.: A Tyrant sent by Umbrella to retrieve Lucia too, he causes the outbreak in both the Umbrella submarine and the Starlight.

Monsters

 * Regular Zombies: The most common enemies, they slash, vomit and bite you at short range.
 * Armed Zombies: Zombies that attack with a crowbar, sometimes at long range.
 * Female Zombies: These zombies can inflict poison, but they are the easiest ones to kill.
 * Captain Zombie: The Captain in Zombie form, he has a gun and he can fire it to deliver heavy damage.
 * B.O.W. (First Form): The first form of the B.O.W, uses his fists to attack.
 * B.O.W. (Second Form): The Second form of the B.O.W, can attack from long range.
 * B.O.W. (Third Form): The third and most dangerous form of the B.O.W, can deliver heavy damage