You are currently viewing OSRS Biohazard Guide (Quick Quest Guide)
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In this OSRS Biohazard Quest Guide, we’ll go through all the steps to complete the quest.

This guide is a part of our OSRS Optimal Quest Guide.

Biohazard story & info


Biohazard follows up with the Plague City story. The rescued Elena needs your help. Her distillator is still in West Ardougne and she needs it to figure out how she can solve the Plague and rescue the people of West Ardougne. During this quest, you will once again infiltrate West Ardougne, poison some Mourners, enter their headquarters as a doctor, kill one of their men, to find Elena’s distillator.

But the quest doesn’t end there. She discovers there is something wrong… The Plague seems to be fake, and you need to help smuggle the results to her teacher in Varrock for a second opinion.


This quest follows up with the Plague City Quest line.

After the quest, you can freely access West Ardougne.

Quest Requirements

skill requirements Skill Requirements

There are no skill requirements.

However, you must be able to kill a level 13 Mourner.

quest requirements Quest Requirements

item requirements Item Requirements

  • The only item you need is the gasmask from Plague City.


  • Teleports to Ardougne
  • Teleport to Rimmington

OSRSGuide Recommendation:

Use the Quest Helper Plugin for Runelite.

The Quest Helper Plugin makes Questing TONS easier.

  • Helps keep track of the item requirements and whether you have them on you or not
  • Displays a quest guide in the sidebar
  • Highlights NPCs you need to talk to
  • Knows which dialogue you need to use during the quest
  • Shows the next location in the quest on your map

If you want to install it, you can install the Quest Helper directly from your Plugin Hub on Runelite.

install the quest helper plugin for runelite from the runelite plugin hub

Biohazard Guide

Quest Start

Speak with Elena in her house (next to her father’s house from Plague City) to start the quest.

speak with elena to start the biohazard quest

She wants to figure out how to stop the plague and needs her distillator. You agree to go back to West Ardougne to fetch it for her.

However, the tunnel we used for Plague City has been filled up. She tells you Jerico can help.

1. Sneaking into West Ardougne

Jerico is located next to the Northern Ardougne bank.

speak with jerico

Speak with him. Then open the cupboard in his house to find some bird feed.

Next, pick up a pigeon cage from behind his house.

pick up a pigeon cage

Now go to the gate to West Ardougne and investigate the watchtower.

investigate the watchtower

Then, open the pigeon cage in your inventory to distract the guards.

distract the guards with pigeons

Now run South and locate Omart on the corner of the wall.

Equip your gasmask and speak with him.

speak with omart to get to west ardy

Omart will help you climb over the wall.

2. Infiltrating the mourners HQ

Once inside West Ardougne, run to the big house in the northeastern corner.

Squeeze through the fence in the back.

squeeze through the fence

Pick up the rotten apple in the yard and use it on the cauldron.

use a rotten apple on the cauldron

Now run to the house in the southwestern corner.

doctors gown location

Search the cupboard to find the Doctors gown. Equip it.

search the cupboard for a doctors gown

Now return to the Mourners Headquarters, this time through the front. You are a doctor after all.

get into the headquarters wearing a doctors gown

Go upstairs and kill the Lvl 13 Mourner. He will drop a key.

kill the mourner guard for the key

Search the highlighted crate to find Elena’s Distillator.

search the crate to find elenas distillator

Now return the Disttilators to Elena. You can teleport to Ardougne or go back toward the wall where you climbed over.

speak with elena and give her distillator to her

3. Smuggling the vials

Teleport to Rimmington (use home teleport if your house is located in Rimmington) OR you can take the boat from Ardougne to Rimmington for 30 GP.

Speak with the chemist, just west of the house portal.

speak with the chemist in rimmington

Now go outside and give your vials to the three lads for them to smuggle inside Varrock.

First, speak with Hops and give him Sulpheric Broline. (option #3)

give sulpheric broline to hops

Then, speak with Chancy and give him Liquid Honey. (option #2)

give liquid honey to chancy

And finally, speak with Da Vinci and give him Ethenea. (option #1)

give ethenea to da vinci

Now teleport to Varrock.

Go to the southeastern pub as highlighted below.

smugglers location in varrock

Speak with Hops, Da Vinci, and Chancy to acquire your vials.

acquire your vials from the smugglers

Once you have spoken to all three men and acquired your vials, speak with Assyf in the clothes shop.

Ask him for a Priest Gown.

speak with asyff to get some priest gowns

Equip both pieces of the Priest Gown.

Now speak with Guidor in the southeastern house.

guidor will test your sample

And guess what? The Plague is fake!

4. Relay the interesting news

Now return to Elena in West Ardougne to tell her the interesting news.

speak with elena and let her know the plague is a hoax

Now finally, speak with King Lathas in his castle and tell him the Plague is a hoax.

speak with king lathas and inform him that the plague is a hoax to finish your quest

And your quest is complete!

Quest Rewards

biohazard quest rewards
  • 3 Quest Points
  • 1,250 Thieving Exp
  • Full access to West Ardougne
  • Access to the Combat Training Camp

Biohazard Quick Quest Guide

If you prefer video footage, check out Slayermusiq’s Quick Guide on Biohazard.


Dean started playing Runescape in 2006 when he was just 10 years old and has been playing ever on and off ever since (you never quit OSRS, right?) In 2013 he switched to OSRS Servers and never looked back. Dean has spent over 20,000 hours in the game now and frequently revisits his favourite portion of OSRS; the early-to-mid game through new account builds. You can also find bite-sized runescape guides on Deans' YouTube channel

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