| Preceded By | Position | Succeeded By |
| Chapter 3-2 | Chapter | Chapter 4-1 |
This battle contains a BOSS BATTLE: Ricardo Irving
After escaping as the oil field explodes, Captain Josh Stone will take you towards Irving via boat. At the beginning of this cutscene you will see the Majini are pursuing you. After the cutscene, there will be two boats on you tail. Pick the Majini off with any gun. Using a sniper and turning around you will see four large oil tanks on top of the bridge shoot them and you will instantly dispatch any majini. Keep your sniper ready and shoot the oil barrel on the wooden bridge and next to a crossbow wielding Majini. After this there will be another majini on your left and another barrel shoot it. Zoom out and you will see two more majini on the bridge again snipe the oil tanks next to them. Once you have past them you will end up in a base with a door blocking your exit. Climb up and take any path left or right but dispatch the majini and you will find oil tanks on the top corners of the base. Before going into the boat there is a BSAA emblem located at the bottom of the door as there will be a hint of silver showing. Once you have opened the door get back into the boat.
Once on the boat shoot the oil barrels and also remember to duck under the pipe. As you proceed there will be another pipe and more oil tanks. After these two pipes you will enter yet another larger base and you will be blocked by yet another door. There will be two gatling guns after you climb up and face left and look up. Take the majini out who are using the chaingun. Pull the levers to open the door. Explore the place and you will find a Benelli M3 shotgun go on the opposite side of the boat and running away from the lever side continue straight until the bridge and you will find a pontoon path leading to the M3 shotgun. Return to the boat and you will travel towards Irving's ship.
This will initate another cutscene, the ship is guarded by majini with chainguns Chris and Sheva dispatch them and they go on the ship while Captain Josh Stone retreats from Irving. Irving has a flashback with birdwoman giving a syringe containing a master Plagas used to mutate Irving to destory Chris and Sheva. Irving mutates with tentacles sprouting from his back it springs him into the water. He rapidly mutates into a gigantic monostrocity.
This boss can be can be extremely annoying. Irving will first have tentacles flailing about on either the left or the right side of the ship. Use any weapon to shoot the tentacles but it is better to use the Gatling gun or the rocket launcher near the front of the ship. The tentacles will have a black mark near the middle shoot that and you will destroy the tentacle but destroy more to attract Irving to the surface. Be careful if you are using the chaingun against Irving's tentacles as you will have to dodge the attacks and get off the Gatling gun at the same time. After attracting him to the surface shoot the weakspot located at the head of the boss and it will attract his attention and you will have to dodge its bite. Repeat this process until another cutscene is shown where Irving himself reveals himself at the back of the ship and uses his tentacles to grab hold. Go to the back of the ship and shoot Irving with the chaingun he will attempt to bite you so dodge and repeat this process until you kill him.
A conclusive chapter cutscene will show with Irving with his dying breath revealing more of the plot.