Before you head out to complete the next story mission (Rescue the Turian Primarch, covered in the next guide) you may want to complete the side missions that you have picked up so far to get a bit of extra experience and a few extra credits to boot. These include the Cerberus Lab N7 mission, as well as the much simpler Shrike Abyssal fetch quest.
The Shrike Abyssal quest begins with an overheard conversation on the Citadel. If you haven’t found it yet, head to the lobby outside of Commander Bailey’s office and listen to the volus speaking to the turian and the human. He will be talking about an important artifact that he has lost somewhere in the Shrike Abyssal area. Collecting this item is a simple matter of finding the right planet. To collect the Shrike Abyssal artifact, the item that the volus was talking about on the Citadel, simply head to the Shrike Abyssal cluster. From here, go to the Urla Rast system and scan the planet called Talis Fia. You will find the artifact. Head back to the lobby in the Citadel and speak with the volus to hand over the artifact and collect 20,000 credits as your reward.
Head back to the Normandy and open up the Galactic Map to begin the next quest, N7: Cerberus Lab. Head to the Mass Relay in Skepsis, in the Sigurd’s Cradle system. Leave Skepsis and fly to Decoris, to the northeast. Land on Sanctum. Add Liara and James to your party, as they will be your only options for now. Be sure to level them up before heading out. At this point, you will have to switch to Disc 2 if you’re playing on the Xbox 360.
On the way to the planet’s surface, Hackett will brief you on the Cerberus lab that is located below you. Cerberus is doing research on the Reapers, as you will have discovered already. You will have to kill the Cerberus agents in the lab and bring the Reaper samples back to the Alliance. The first artifact will be straight ahead of you, on the upper floor and on the other side of the windows. Turn around and go up the steps. Head through the door and look directly to your left. You will find a Sniper Rifle Mod in the corner. There are plenty of other collectibles here, but enemies will begin to file in now so you will have to leave them for later. Kill the Cerberus soldiers and pick up ammo from the cache and credits from the console on the front wall. More credits rest on the console to the left of the entranceway. Salvage the Medical Station in the crevice to the left for 50 experience points, then search the computer in the back left of the room to find a Journal Entry.
When you are ready to proceed, head to the console to the right. Examine the holographic display here to begin bypassing it. You will begin collecting data on the Reapers, and an artifact sample will emerge from the console. Pick it up. Head down the stairs to the right. Examine the computer at the far end of the room to find another journal entry, the companion to the first journal that you found. Loop up the next staircase to your right and head left to find credits resting on the console. Head through the door and interact with the dropship to hand over the first sample, and locate the second. It will be back down in the room you just exited from. As you locate the second artifact, more enemies will begin to pour in from doors to the right and left. Watch out for the Combat Engineer, who will set up turrets at the perimeters of the battlefield and can become annoying if not dealt with quickly. Also be on the lookout for the heavily armored Centurions, who will chuck grenades in your direction and who will take Biotics or concentrated gunfire to bring down.
Bypass the console in the back of the room to collect a second Reaper artifact. As you bypass the console, two more enemies will rappel in from the ceiling. Kill them quickly. After the bypass has been completed, you will receive an urgent message from Cortez. His dropship has been discovered by Cerberus, and he will have to shake them before you can return the artifact to him. Waves of Cerberus soldiers will begin to pour into the area. You will have to survive until Cortez loses his tails in order to beat this mission. There will be infinite waves of enemies, many of whom will be shielded or armored, or will spawn turrets. Find a good place to hold out – the curves of the computer consoles makes for a good temporary fort, which you can escape easily if things get hot – and hold out until you receive the radio message that the coast is clear.
Stick with your teammates here, as they can easily go down in a hail of concentrated gunfire, especially Liara. The enemy forces can easily become overwhelming if you venture outside of your cover or leave your teammates to their own devices. Use Biotics liberally and intelligently, and make good use of the ammo cache in the room with the first Reaper artifact. When Cortez finally arrives with the ship, he will ask you to clear out the landing pad. Take cover on the upper floor and fire down upon the Combat Engineers, who will have assembled a few turrets as well. The turrets, combined with the foot-soldiers, are surprisingly adept at whittling down your health at a fast rate. You can take them out fastest with the Sniper Rifle. Use Singularity to take out any enemies clustered on the stairs. When they are all dead, run over and get on to go back to the Normandy. Admiral Hackett will congratulate you on your victory and pledge to examine the artifacts, and you will receive 3,000 credits.
