The Parasitism 5 contract is a priority task to complete for the Sekiguchi faction in Marathon, and it’s a collection of three different activities.
Parasitism 5 is the final contract in the series, and this guide will help you complete all three tasks.
Marathon Parasitism 5 contract walkthrough
The Parasitism 5 contract can be broken down into three tasks.
- Extract biotic sample from Sparkleaf in Bio-Research
- Synthesize SIMbiont in Quarantine and inject yourself
- Allow the SIMbiont to integrate with your shell; then exfil
For the first task, head to the Bio-Research location in the northern area of the map. You’ll first need to pick up Sparkleaf that can grow among vegetation.
They don’t have a specific location, but they’re fairly common. Once you find a Sparkleaf, head to the marked location in the image below.

You’ll find an extraction machine to extract a biotic sample from the Sparkleaf (place it in its inventory and then wait for a few seconds).

How to synthesize SIMbiont in Quarantine and inject yourself

Pick up the sample and head to the southwest part of the map, where you’ll find the Quarantine POI. I have marked the location where you’ll find a small room with the terminal inside (will be highlighted by a quest marker when you’re at the marked spot).

Access the Synthesizer and place the sample to get the SIMbiont. Inject yourself with the item and then wait for 1 minute and 30 seconds. You’ll need to survive a UESC onslaught as the SIMbiont integrates with your shell. Once you manage to survive the 90 seconds, safely exfil from the map, and you’ll complete the final Parasitism contract in Marathon.






