No, we’re not talking about the original Japanese title of the Resident Evil games–this is about that Old School RuneScape Quest called Biohazard. It’s a rather long and tricky quest, so a guide would come in handy. You wouldn’t be here if you’re looking for one, so read up!
Before You Cross the Border
Before you can start with the quest, you have to first the Plague City quest first. If you want to finish that quest right away so you can already start with this one, you should check out other guides.
You also need a Priest Gown top and bottom, as well as a gas mask. If you want to get one for free, you can acquire one in Edmond and Alrena’s house in East Ardougne.
Also, while not exactly hard requirements, it’s preferable to be able to Teleport and have some energy or stamina potions. They’re worth the OSRS gold you’ll need to spend for the sake of convenience.
With the Birds
To start the quest, you need to talk to Elena in East Ardougne. She will tell you to talk to Jericho, her father’s friend.
He’s been communicating with West Ardougne through pigeons, so it makes sense that he’s going to ask you to get a pigeon cage and bird feed. The former is behind the house, and the latter is in the cupboard.
So you won’t be confused by the guide, here’s a bit of context: the capital, Ardougne, is split into two: East and West. As the quest’s name suggests, the latter is afflicted with a plague. If you’ve already finished the Plague City quest, you’d already know this.
Going back, you should speak to Omart after that. You’ll find him in Ceril Carnillean’s house, which is southwest of the castle. He’ll tell you that you’ll have a hard time entering the city because the guards are too close to the wall. For that, you’ll need a distraction, which is why you have to head to the small watchtower by the wall, which is directly north.
Once you’re there, head towards the point that the two fences converge. The bird feed must be put on either fence. After that, click on the cage. Omart will then call Kilron, his assistant, to give him the rope ladder. Climb it and you’ll be able to get to West Ardougne.
Distracting the Mourners
Upon crossing to the plague-stricken half of the capital, go to the Mourner’s HQ. You will, however, not be allowed to enter, as they will be eating stew. To get in, you need to distract them. How? By dropping a rotten apple on the stew that’s being cooked in the backyard. To get the fruit, you need to squeeze through a gap in the fence and get the apple on the ground near it.
The mourners will then inform you that many of them have been stricken with food poisoning and are in need of a doctor. That’s your cue to go to Nurse Sarah’s house, who’s in a building southwest of the West Ardougne Church. There, you’ll find a medical gown. Wear it and you’ll be able to enter the Mourner’s HQ. Once you’re in, kill one of the mourners, find Elena’s distillatory in one of the crates, then go to Kilron, who’s southeast of West Ardougne, to return to East Ardougne.
Uncovering the Truth
For the next part of the quest, you’ll be going to Rimmington. Preferably, you can teleport to Falador, Draynor Village, or the cabbage patch. Once in Rimmington, go to the southwest corner, where you’ll find the chemist. He’ll give you the chemicals necessary for the quest. You’ll be giving them to the three errand runners namely Chancy the Gambler, Da Vinci the Artist, and Hops the Drinker.
After that, equip a priest gown set then go to the fenced area southeast of Varrock. You can get one from either Thessalia’s Fine Clothes for 10 coins or Fancy dress shop owner at the north of Guidor for 12 coins. The guard will confiscate the vials but not the plague sample. With the plague sample, go to the Dancing Donkey Inn and talk to the three you gave the vials to.
With the priest gown equipped, head to Guidor’s house, which is southeast of the gated area. Give to Guidor the vials and sample, and tell him about Elena needing a sample. After confirming that the plague is a hoax, return to Elena in Ardougne, go to King Lathias at the East Ardougne Castle. He’ll then tell you all about the entire conspiracy.
Doing the Biohazard quest these days like is rather timely. So, what are you waiting for? Pick the quest up now and experience what an epidemic is like in Gielinor!