I ran into Bio-Research with the Sparkleaf already burning a slot in my pack and realized the terminal I needed was one stair too far. The run narrowed to a single decision: climb the ladder and hope the marker appears, or bail and lose the contract. You feel the clock in your hands—every second in Marathon matters.
I’ve finished Parasitism 3 more times than I’d like to admit, and I’ll walk you through the one run that keeps the contract tidy: grab a Sparkleaf, process it in Bio-Research, inject it in Central Quarantine, and leave without a scratch. I’ll point out traps, the exact terminal position, and why the Sekiguchi faction cares about this sample. The map is a clockwork maze, and knowing the tiny gears saves runs.
You’ll see Sparkleafs spawn along popular paths on Dire Marsh before you even hit the POI. Marathon Parasitism 3 contract walkthrough
There are three tidy tasks to finish in a single run:
- Loot a wild Sparkleaf in Dire Marsh
- Extract the Biotic Sample from that Sparkleaf at the Bio-Research terminal
- Inject the synthesized sample in Central Quarantine, then exfil
Where can I find Sparkleaf in Dire Marsh?
You don’t need a fixed spawn to finish task one. Sparkleafs appear randomly across the marsh; they’re common enough that you’ll spot one on most passes if you sweep the usual routes. When you see the plant (the image above is what you’re after), pick it up and don’t waste extra detours—the rest of the run depends on reaching Bio-Research with that item in inventory.
How do I extract the Biotic Sample in Bio-Research?
Head to the Bio-Research POI on the eastern map edge. The building shown above is your target. From the main approach take the ladder at the building’s side up to the upper floor. At the top, step through the door immediately to your right—the Biotic Sample terminal sits in that room.
Stand in front of the terminal, interact, and place the Sparkleaf into the processing slot. The terminal will spin a short animation and flag the extracted Biotic Sample in your inventory. If the marker fails to appear, back out and re-enter the building; the objective triggers when the server registers your interaction. The terminal is a scalpel—small and precise—so don’t skimp on positioning when you interact.
How do I inject the synthesized sample in Central Quarantine?
Make your way to the Central Quarantine POI and enter the small room marked on your map. The quest marker will highlight the terminal location. Insert the extracted Biotic Sample and wait for the synthesis animation—this converts your item into the injectable form the contract wants.
Inject the synthesized Biotic Sample into your character when prompted, then leave the map without dying to complete Parasitism 3. If you die after injection the run won’t count, so pick a safe exfil route. Bungie’s spawn and marker quirks sometimes force a quick sprint; plan your escape before you interact.
If you still want a fast checklist to run from memory: grab Sparkleaf in Dire Marsh → climb Bio-Research ladder → interact with terminal and extract → go to Central Quarantine → place sample, inject, exit. I used these steps while testing with Moyens I/O screenshots for clarity—would you change your route after one testing run? ?