Dr. Katsumi Safe Code (The First Biomarker)
In the side quest, "The First Biomarker," in Dying Light 2, players must solve a riddle given by Dr. Katsumi in order to get the safe code.
After completing the main quest "Markers of the Plague" in Dying Light 2, the side quest "The First Biomarker" will become available. In this side quest, players will need to revisit the Saint Joseph Hospital to find a special Biomarker said to make humans faster and stronger. "The First Biomarker" can be started by heading to the Trading Post in Trinity near the Alder Windmill and speaking to McGregor.
Players will only need to complete the third mission in Dying Light 2 in order to start the side quest. After speaking to McGregor, players will need to go to Saint Joseph Hospital to search for the special Biomarker he invented. McGregor will give players a note written by Dr. Katsumi who locked his enhanced Biomarker in a safe. After obtaining the note, it can be viewed in the collectibles menu at any time. The hospital is located just across the street from where McGregor is.
The objective marker should take players straight to Dr. Katsumi's office on the top floor. There are three riddles to solve from Dr. Katsumi's note, one for each digit in the safe code. Although the safe combination lock goes from 0 to 99, each number in the code is only one digit. The three riddles can be solved by paying attention to the wording in each phrase and associating a number with it.
Solving the Riddles for the First Biomarker Safe in Dying Light 2
Like completing the GRE Quarantine Buildings in Dying Light 2, players will receive an inhibitor for this side quest that can be used to upgrade Aiden's health or stamina. The first riddle for Dr. Katsumi's safe code is, "What becomes smaller when you turn it upside down?" The number players are looking for is nine, which becomes six when flipped upside down. The second riddle, "An odd number - take away a letter and it becomes even," is a little less straightforward. The riddle refers to the number seven, which, when the 's' is taken away, becomes the word 'even.'
The final riddle states, "A little girl goes to the store and buys one dozen eggs. As she is going home, all but three eggs break. How many eggs are left unbroken?" This riddle is meant to confuse players simply because it is unnecessarily wordy. Since all but three eggs break, that means three eggs are left unbroken. With all the riddles solved, players can interact with the safe and enter the code to continue with "The First Biomarker" side quest.
The riddles give players the code 9-7-3, and entering it will open the safe in Saint Joseph Hospital. After retrieving the contents, Aiden will automatically use the Biomarker. Players will then need to fight a few of Dying Light 2's infected, but they are low-level enemies and should be easily defeated. McGregor will be angry that Aiden used the Biomarker, but he still offers an inhibitor as a reward for retrieving it. "The First Biomarker" side quest includes one of several safes that can be opened by solving riddles in Dying Light 2.
Next: Dying Light 2: The Essence of Survival Guide (Dialog Choices & Answers)
Dying Light 2 is available for Xbox One, Xbox Series X/S, PlayStation 4, PlayStation 5, and PC.
