Operation Plague Star is an event in Warframe. During Plague Star, the Plains of Eidolon become infested with a huge boil. It is up to the Tenno to clear the boil from the Plains and save Cetus from the Infestation which threatens to roll over it like a tide.
How To Take Part In Plague Star
To take part in Plague Star, you need to visit Konzu at Cetus. He will have a special bounty you can do as part of the Plague Star event. This bounty involves you stealing some Grineer Toxin, mixing it up, and using it to poison and aggravate the boil. This is a four-step bounty.
You need to go and steal the Toxin. This is very simple, go to the cave on marked by the waypoint, kill the bad guys, and grab the Toxin. This is a very low level, so you shouldn’t have any issues with it.
Travel to the point marked on the map. This is where you will find the Toxin Mixer. Load the Toxin into the mixer and then defend the area until it is done. This will take three minutes, and Grineer enemies will arrive by drop pod and by ship. Just wipe out the waves as they arrive.
At this point, you can add Eidolon Phylaxes (blueprint is available from Nakak in Cetus) and Infested Catalysts (blueprint is available from the Bio Lab in the Dojo) to the mixer, if you like. This will increase the difficulty of the fight at the end, but shall also increase the Standing you get from it.
When the Toxin has finished mixing, you need to attach it to the Drone to carry it to the boil. Just go to the waypoint and interact with the Drone when you are carrying the Toxin to load it up. After that, follow the Drone, just like any other Drone escort mission. It will lead you to the boil.
Sometimes, the Drone might get stuck on some terrain. If you are worried about this, run as Loki because you can displace the Drone using his Switch Teleport ability.
Time to fight some monsters! The Drone will poison the boil, and a progress indicator will start to tick up in the top left corner of the screen. You need to clear out waves of Infested to keep the progress bar going, and potentially fight a huge Hemocyte that will spawn from the boil. Depending on how many Infested Catalysts you added to the Mixer, the Hemocyte can spawn up to four times and will pause progress each time it spawns until you defeat it. If you don’t add any Catalysts, then it shouldn’t spawn at all.
When the progress counter hits 100%, the boil is defeated, and the bounty is done. At this point, you can return to Cetus and rerun the Bounty if you so choose.
Important Information About Plague Star
Nakak runs a Syndicate during this event called Operational Supply. You can rank up with them as you do any other Syndicate, so check in with him regularly to rank up. This is also where you can get great rewards like the Plague Kripath and the Plague Kewar if you have enough standing. These items are very much worth grinding for.
If you are curious as to what the Hemocyte Cystolith is, I have a quick guide for that ready for you. Also, If you are struggling to kill the Hemocyte, you can find a full guide filled with useful information here. Best of luck Tenno!