Control Resonant: New Growth Side Quest Walkthrough

In Control Resonant, New Growth sends Dylan through The Park to locate Dr. Raya Underhill, the Mold program’s lead scientist, who is currently missing. The search starts at an FBC outpost, continues to her former office in the Oldest House and then her apartment, and ends below ground in a hidden sewer lab where her escaped Test Subjects are hiding. Finishing the quest awards Untapped Brass Dusters and contributes to the Budding Mycologist trophy and achievement.

Quick answer: Talk to Ranger Busken at the FBC Base, grab the Level 6 Keycard, read the Welcome Letter in her office for the address, meet Underhill at 140 Fletcher Ave, then clear the sewer lab, defeat Specimens A, B and C, and choose “Take the samples.”

New Growth rewards

Your primary reward is the Untapped Brass Dusters, an upgrade form for the Aberrant melee weapon. Quest completion also grants a Mold Sample Test Tube, and you can collect a Power Upgrade Point while inside the lab.

Reward	Where you get it
Untapped Brass Dusters	Choosing “Take the samples” at the end
Mold Sample Test Tube	Quest completion
Power Upgrade Point (2/3)	Inside Underhill’s Sewer Lab

Completing New Growth also progresses the Budding Mycologist trophy and achievement. That reward needs both New Growth and the Carbon Copy questline finished before it pops.

How to start New Growth

There are two ways to begin. The quest starts on its own once you finish the Zoe’s Briefing side quest, where Zoe brings up Underhill’s disappearance. If you skip Zoe’s Briefing, you can pick it up directly by speaking to Ranger Busken, the soldier on the rooftop of the FBC Base in The Park.

Restore power to the elevator to access the FBC Base roof, or use the sewers northeast of The Park. The sewer route brings you out onto the street east of the base, where you can jump onto the roof.

Track down Dr. Underhill in The Park

Mark The Park Checkpoint on the Central map and cross it on foot. Clear the hostile Mold organisms in the quarantine streets and push through the quarantine facility to reach the rooftops.

Use the Park Valley Fast Travel Door, then battle the Mold-infected hosts on your way to the FBC Base. Activate the FBC Base Fast Travel Door when you get there.

Speak with Ranger Busken at the base. He explains that Underhill vanished at a nearby research site, which updates your objective to examine where she was last seen.

Cross the rooftops heading south until you reach her abandoned field outpost. Take Underhill’s Resignation Letter and the Level 6 Keycard from the workstation table.

Search the office and apartment

Ride the elevator to the Oldest House, then travel to Central Executive. In the Executive Research wing, unlock office 06 with Level 6 clearance to enter her former room. Go upstairs, then turn left to find the door.

The Welcome Letter on the desk gives her rental address: 140 Fletcher Ave. Pick up Underhill’s Apartment Key from that desk as well.

Use the Central Executive fast travel door to return to The Park, then take the streets to the apartment building in the area’s upper-right section. Defeat the Mold enemies guarding its entrance.

Climb one floor and go through the first door on the left. Collect the Research Notes On The Mold, then speak to Dr. Underhill in the kitchen. She gives you the Key to Underhill’s Sewer Lab and asks you to bring back her escaped Test Subjects.

Clear the sewer lab and start the trail

Exit the building, turn left, and go around the corner to find the sewer drain on the apartment’s northeast side. Descend underground, take a left at the intersection, and unlock Underhill’s Sewer Lab with the key.

Pick up the Mold Growth Stimulator and Sample Tubes by interacting with the table on the right. While in the lab, also collect the Response From Pope document and Power Upgrade Point (2/3).

Use the stimulator on the throbbing Mold clumps beside the table. They pursue the escaped Test Subjects, leaving glowing spore trails to show where they went.

Drop down beyond the railing into the deeper pipe system and follow the trail. When it splits, the branches lead to the separate specimens.

Defeat all three Test Subjects

Each specimen begins as a mold trail. Follow it until the mold turns into an enemy, then destroy it and harvest a Mold Sample Test Tube from the kill. Fire damage is effective against these creatures, so Inferno is a strong pick if your build has it. Their locations are fixed, and the order you clear them does not matter.

Specimen	Location
Specimen A	Airborne, in the flooded tunnels
Specimen B	In an alley at street level, accessible with a jump across The Park rooftops
Specimen C	Trapped in the exposed maintenance yard beside the orange-lit drainage route

A cloud marked with an exclamation point on the map indicates the next Test Subject. Trace each trail to the spot where the Mold forms into an enemy, defeat it, and take its sample. After all three Mold Sample Test Tubes are in your inventory, the objective directs you back to Underhill.

The Underhill choice and quest completion

Run back to the apartment and speak with Dr. Underhill. The final conversation gives three options: “Take the samples”, “I have to report you”, and “Go… without the samples”. The choice decides Underhill’s fate. Report her and the Bureau takes her away; let her leave and she is free to continue her work. None of these outcomes change the rewards or block the achievement, so pick whichever ending you prefer.

Select “Take the samples” to give Underhill the collected Mold and allow her experiments to continue. The “QUEST COMPLETED / NEW GROWTH” banner appears, and your inventory receives the Untapped Brass Dusters and a Mold Sample Test Tube, confirming completion. In the weapon menu, equip the Untapped Brass Dusters as an Aberrant form upgrade to use the new melee form immediately.