The Return on Investment 3 contract is one of the most structured priority tasks the Traxus faction hands you in Marathon. Three separate objectives, all completed within a single run. No checkpointing between them, no second chances if you wipe mid-mission. That pressure is exactly what makes finishing it so satisfying when you pull it off cleanly.
What Is the Return on Investment 3 Contract?
The Return on Investment 3 contract is a Traxus faction priority task in Marathon. It asks you to complete three distinct objectives back to back during the same deployment:
- Download a UESC Comms Security Code in the Quarantine zone.
- Defeat the UESC Commander in Maintenance and collect credentials from the body.
- Intercept UESC comms at either AI Uplink or Bio-Research.
All three must be finished on the same run. Planning your route before dropping in will save you a lot of stress.
Because all three tasks must be completed in a single run, plan your movement across zones before you start. Dying between objectives resets your progress on the contract.
UESC Comms Code terminal
How to Download a UESC Comms Security Code in Quarantine
The first objective sends you to the main building in Quarantine. Head through the main entrance and make your way to a room on the ground floor where a terminal is waiting. Once you get close enough to the correct spot, a quest marker appears to point you directly to it.
Interact with the terminal to download the UESC Comms Security Code and the first task is done. This is the most straightforward of the three objectives, so treat it as your warm-up before things get more involved.
Clear any enemies near the terminal before interacting. You are vulnerable during the download animation, and getting hit mid-interaction can cost you precious time.
How to Defeat the UESC Commander in Maintenance
The second task takes you into the Maintenance zone. Enter from the south entrance and follow the pink quest marker to the UESC Commander's location. The marker appears reliably once you are inside, so navigation here is simple.
The fight itself is manageable, but positioning matters. Fighting the Commander from an elevated spot reduces the number of hits you take, since the enemy's attack patterns are easier to avoid when you have height advantage. Once the Commander goes down, loot the credentials directly from the remains to complete the second task.
Do not rush into the Commander's room without checking for additional enemies. Adds in the area can overwhelm you if you engage the Commander with threats on multiple sides.
UESC Commander fight location
How to Intercept UESC Comms at AI Uplink or Bio-Research
The final objective gives you a choice: head to AI Uplink or Bio-Research. Either location works for the contract. AI Uplink is a solid pick if you want a clear route with predictable geometry.
At AI Uplink, your target is the top of the catwalk structure. Use the ladders positioned near the catwalk to climb up onto the cables that form the roof of the catwalk. The interactable item to intercept the comms is located up there. The quest marker activates early once you are in the right general area, so you will know when you are on the correct path.
Complete the interaction and the Return on Investment 3 contract is finished.
Return on Investment 3 contract tasks
What's the Best Route to Complete All Three Tasks?
Efficiency is everything when all three objectives need to land in one run. Starting with Quarantine first makes sense since the terminal interaction is fast and low-risk. From there, moving into Maintenance to handle the UESC Commander keeps momentum going. Saving the AI Uplink intercept for last works well because it sits naturally at the end of a logical movement path through the map.
Bring a loadout that handles mid-range encounters reliably. The Commander fight is the biggest threat to your run, so having enough firepower and healing to push through that encounter cleanly is the priority. The other two tasks are largely about navigation rather than combat.
The quest markers for each task appear dynamically as you approach the correct zones, so you do not need to memorize exact coordinates. Getting to the right general area triggers the markers automatically.