《Resident Evil 9: Requiem》 East Wing Walkthrough: Obtaining the Sun Quartz

With the red gem, you can now open the door to the West Wing reception room. Note that the Chef patrols the corridor now, so you'll need to sneak past him. Inside the reception room, you'll find the East Wing Keycard in the hand under the table, which grants you access to the East Wing.

It is recommended to spend any collected Ancient Coins here to upgrade Grace's attributes, as this will make the rest of the game much easier.

Upon entering the East Wing lobby for the first time, the only path forward leads to the Examination Room. On the operating table lies a body with its organs removed, which also serves as the tutorial point for the Hemorrhage Syringe — this item can permanently kill any zombie in your path, including the Chef, with one shot.

From the other end of the corridor in the Examination Room, you'll reach the Blood Lab. Here, you can obtain the Blood Collector and Modified Blood Sample, unlocking the ability to craft infected blood items. While this part is optional, it is highly recommended for a first playthrough as it will save you a lot of trouble.

Return to the corridor with the zombie that turns off the lights, turn left into the stairwell, and go up to the Lead Researcher's Office. Inside is a locked puzzle box that requires Corrosive Fluid from the meeting room to open. Be sure to examine all the paintings in the room; the archives contain hints for the puzzle.

Leave the Lead Researcher's Office and follow the corridor on the left to pick up the Level 1 ID Wristband. Remember to free up an inventory slot before picking it up.

Afterwards, you can return to the Examination Room or enter the waiting room through the opening on the left below the stairs to go straight back to the East Wing lobby. In this area, you'll encounter a new enemy: the "Blockhead". You can take him down with a few rounds of Requiem ammo or 3 Hemorrhage Syringes.

Sneak past the Blockhead's patrol area and enter the room behind the ID wristband pickup point to reach the meeting room. There's an annoying Opera Singer enemy inside; carefully sneak past, grab the Corrosive Fluid, and get out quickly.

Bring the Corrosive Fluid back to the Lead Researcher's Office, enter the code: Star → Sun → Moon → Sun, open the puzzle box, and obtain the Sun Quartz and Leather Notebook (be sure to examine it). Then return to the Guard Room to organize your inventory, and insert the Sun Quartz into the large door in the main hall.