Biohazard Quest Guide

Skill Requirements: None

Quest Requirements:

  • Must have completed Plague City

Required Items:

  • Priest gown top
  • Priest gown bottom
  • All other items needed for this quest are obtained during it.

Other Requirements:

  • You need to be able to kill a level 13 mourner.

Quest Start: To start this quest, talk to Elena who is found in East Ardougne.

Reward: 3QP, 1250 Thieving XP, access to King Lathas' training field

Step 1: Starting the quest

Speak with Elena who is found in East Ardougne, in a building on the north-west side of the city.

She mentions that the mourners have confiscated her testing equipment.

Tell her that you will retrieve the equipment for her, to which she'll be grateful.

Unfortunately, however, you will not be able to enter West Ardougne using the tunnel as before. You will need to find another way into the city.

She goes on to tell you that her father's friend, Jerico, might be able to help you get inside the city.

Step 2: Speaking with Jerico

From Elena's house, head east across the log balance (or the long way through the entrance of the castle) and go to the house directly south of the north-most bank. This is Jerico's house.

Go inside and speak with Jerico. He tells you that a friend of his, Omart, will aid you over the wall into the city.

While you are inside Jerico's house, search the cupboard for some bird feed. Also, take a pigeon cage which can be found behind his house.

Omart is located south of the castle, near the wall.

Step 3: Speaking with Omart

Speak with Omart. He tells you that he's ready to help you over the wall; however, you must first find a way to distract the guards.

He informs you to go back and speak with Jerico, who might be able to help if he's not too busy.

Note: Don't bother going back to Jerico's house, as he will indeed be too busy to help you.

Step 4: Distracting the guards

Head north to the Watchtower with some mourners near the building with the wilderness lever.

Use the bird feed you obtained at Jerico's house on the Watchtower.

Once you've done that, open up the Pigeon cage. The pigeons will fly toward to Watchtower, successfully distracting the guards.

Step 5: Getting over the wall

Head back to Omart, and speak with him. He'll inform you it's now or never to get over the wall and he'll call his associate to throw over the rope ladder once you agree to go.

Step 6: The Rotten apple

Once inside the city, head over to the Rehnison home (from the Plague City quest) and pick up the Rotten apple which is located just north-east of their house.

Once you have the apple, squeeze-through the fence of the building just east of the Rehnison's house.

Use the apple with the Cauldron and attempt to enter the back door of the building.

You will be stopped by a mourner who tells you that you cannot enter, as many of the other mourners are sick from food poisoning and are awaiting a doctor.

Step 7: Help is on the way!

Exit the building by squeezing-through the fence again, and head to Nurse Sarah's residence, which is located south-west of the altar.

Search the cupboard for a Doctors' gown, and then head back to the building with the sick mourners.

Try entering through the front door with the Doctors' gown on, and you will be let inside, as you're suspected of being the Doctor.

Step 8: Retrieving Elena's equipment

Open the door to the west side of the building and go upstairs.

Kill one of the mourners for a key, and use that key on the locked gate. Search the crates until you find Elena's Distillator.

Once you have the Distillator, return to Omart's assistant, Kilron, and tell him you're ready to go back into East Ardougne. You will then climb over the rope-ladder.

Step 9: Testing some samples

Head back to Elena and speak with her. She tells you that she wants you to go see Guidor, who lives in Varrock, to bring him some vials and a sample.

However, she first wants you to collect some more touch paper from the chemist in Rimmington.

Note: It's important that you do not engage in any fights or teleport while you have the sample and vials in your inventory. They will be destroyed if you do. If you want to teleport to speed up your travels, bank the vials and sample first.

Step 10: The Chemist

Head to the Chemist, who can be found west of Rimmington.

Once you are there, speak with him.

Note: It's important you choose the correct dialogue; otherwise he will confiscate your vials and sample!

First tell him that you're here for a quest. At first he seems hesitant to help you, but then tell him you're friends with Elena.

Finally, tell him you are in need of some touch paper for a guy called Guidor.

He gives you the touch paper, and tells you to give the potions over to his errand boys who can be found just outside.

Step 11: The Errand boys

There are three errand boys: Hops, Da Vinci and Chancy. They each need to be given one of the three vials.

Note: It's important that the correct potion is given to the correct errand boy. Follow the instructions below carefully.

  • Give Hops the Sulphuric Bromine (green vial)
  • Give Da Vinci the Ethenea (clear vial)
  • Give Chancy the Liquid Honey (dark gold vial)

Step 12: Getting to Guidor

Once you have given each of the errand boys the correct potion, head over to Varrock.

Note: Once again, do not teleport with the plague sample in your inventory. If you want to teleport, bank it first.

Go to the south-east gate inside the city, wearing the Priest gown top and bottom. A guard will quickly search you but let you pass.

Once you are past the gate, enter the bar and speak with each of the errand boys to retrieve your chemicals.

After you have retrieved the chemicals, go to Guidor's house, which is just south-east of the bar.

Speak with him and tell him you've come to request his assistance in stopping a plague.

He'll respond shocked, but inform him that you're good friends with Elena. He'll accept your response and then get to work on the sample. Give him all the vials and sample and he will test it.

Moments later he concludes that something doesn't add up. Ask him what exactly he means and he'll tell you that there really is no plague.

Step 13: Finishing the quest

Head back to Elena's house and inform her of Guidor's findings. She tells you that you need to report this to the King immediately.

Head south from Elena's house to the Ardougne castle and go upstairs and speak with King Lathas. After some quick conversation, he confesses that he faked the whole plague “for the good of [his] people”.

He goes on to say that lying to the people is actually protecting them from a far greater danger, which he goes on to explain once you say that you don't understand. He then asks if you will support him when that danger arises, which of course you agree to.

You are given access to his private training ground, and you finish the quest.


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