First, you need to explore the West Area of the Lab.
Looking for something else? Visit our Resident Evil 2 walkthrough for more help.
Exploring the West Area of the Lab
Back in the Main Shaft, unlock the West Area and grab the Lab Digital Video Cassette from the corpse at the entrance of the Biotesting Lab.
Use the Signal Modulator on the wall tuned to OSS (Red at 12 O'Clock, Green at 4 O'Clock) to restore the power to the room, allowing you to proceed.
You can also access the PC for the William Birkin's Inbox File as well as use the video tape on the recorder next to the Item Box.
The route on to the P-4 Testing Lab at the end from here is now pretty straightforward.
Read the PC as soon as you enter left for the Research Diary file, then grab the virus from the end machine. Be sure you have done everything you want to do in the lab before so though - as this is the game's final point of no return.
An alarm will sound when you take the sample, but there's no rush in getting out of there - use the Typewriter in the room to the north, and get prepared for a battle, and proceed the way you came.
Playing the DLC? Check out our list of Ghost Survivors Mr Raccoon locations. Elsewhere, our full Resident Evil 2 walkthrough explains every aspect's of Leon and Claire's campaigns, including C4 Detonator and Battery locations, Heart Key location, how to stop Mr X, the Clock Tower puzzle, Sherry block puzzle in the Orphanage, the Power Panel Parts puzzle solution, how to escape the Incinerator and the Chess Plug puzzle solution. Not only that, we also provide all Locker Code solutions, the Leon Desk puzzle solution, all Resident Evil 2 Safe Codes and Portable Safe solutions and the Hiding Place locations.
G Tyrant (Stage 3) boss strategy
The G Tyrant has now grown more eyes across its body, including its back. You have to shoot at each one in order to stun it, revealing a central mass of eyes from its chest, which you must also shoot. You need to repeat this cycle until it's eventually downed.
Problem is, this stage of the G Tyrant is more aggressive than previous states, so keep a fair distance away from it, allowing you dodge its lunges. It also picks up objects from around the room and throws them in your direction - when it does, find cover until it does so.
Its aggression comes in handy though, as after each attack or as it prepares to throw something, it'll pause, leaving its eyes open to attack. This is particularly useful for using the Magnum - a deadly but very precise weapon.
We recommend using the Shotgun on the move as you'll want to be less accurate, and using the Magnum to as it just finishes an attack or prepares to throw something.
After the second bout of damage at its chest, it'll start charging around with the eyes exposed. It'll be harder to get precise damage at this point, so we recommend using the Shotgun if you're struggling. Additionally, at the start of this phase, it'll pull the panel from the wall - when it does, run to the sides to avoid getting slammed.
Keep mobile and damaging it in this final part until it's downed. Remember there will be consumables appearing all round the edges of the arena if you need ammo and health - and to mop up all of these when the battle is over before you get the lift.
After you take the lift, head towards the Main Shaft. After the cutscene, take it down and you'll have ten minutes to escape - and take on Resident Evil 2's final boss.
Will you support Eurogamer?
We want to make Eurogamer better, and that means better for our readers - not for algorithms. You can help! Become a supporter of Eurogamer and you can view the site completely ad-free, as well as gaining exclusive access to articles, podcasts and conversations that will bring you closer to the team, the stories, and the games we all love. Subscriptions start at £3.99 / $4.99 per month.