Biohazard

Biohazard continues the storyline after the Plague City quest. The plot deepens as Elena finally gets a chance to process her plague samples. Buried under these samples, lies a well-hidden secret.

Confiscated
To begin, go to Ardougne and talk to Elena in East Ardougne, in the house east of her parents. She will tell the player that she was able to collect some good samples of the plague, but unfortunately the Mourners took all of her equipment and locked it away at their headquarters. She now needs someone to sneak back into the city and try to find it for her. Since the sewer tunnel used in the previous quest has been sealed off from the other side, she suggests talking to her father's friend, Jerico, who keeps communication with West Ardougne via his pigeons.

Sneaking Back
Jerico lives in a house just south of the northern bank in Ardougne and just north of the chapel. He will tell you that he has arranged for Omart to help create a rope ladder to get over the wall between the cities.

Omart can be found west of Ceril Carnillean's house in East Ardougne, just south of the castle. When you talk to him, he says that although he can move you over the wall, it is too risky as the watchtower guards are too close to the wall. The guards need to be distracted so that you can find an opportunity to enter the city. He will tell you to talk to Jerico.

Return to Jerico and talk to him, then search the cupboard nearby to find some bird feed and grab a pigeon cage from the backyard.

Now head to the watchtower, directly north of Omart. Stand in the corner where the two spiked fences meet and use the bird feed on the watchtower fence. Once the feed is in place, open the pigeon cage to release the pigeons. The pigeons will immediately fly to the watchtower, to eat the feed, and distract the guards.

Go back and talk to Omart, who will call out to his assistant, Kilron, to throw over the rope ladder. Climb over the ladder into West Ardougne.

Infiltrating Mourner HQ
Head to the Mourners' Headquarters located in the north-eastern corner of the city. Try to enter, but you will not be allowed in by the mourners. Go around the headquarters to the northern part, where you can see a cauldron being cooked in the backyard. Pick up the rotten apple laying on the ground just to the west, and squeeze through a gap in the fence into the backyard.

Use the rotten apple on the stew that is brewing in the cauldron. Squeeze back through the fence and walk around to the front of the building, and attempt to go inside again. One of the mourners will tell you that the player is not permitted inside because several mourners are ill with food poisoning, and are waiting for a doctor.

Head to Nurse Sarah's house - the large building south-west of the West Ardougne church. Search the box in the northern part of her house to obtain a doctor's gown. Equip the gown and go back to the headquarters. The professional attire will easily fool the mourners into letting you into their base. For all subsequent visits to the headquarters during the quest, the gown must be worn at all times.

Go upstairs and kill a mourner, while still wearing the doctor's gown. The key will automatically be placed in the player's inventory. Use the key on the gate to get inside the caged room. Search the crates to find Elena's distillator.

Exit the headquarters and head back to Kilron at the south-east corner of West Ardougne. He will help the player get back over into East Ardougne. Alternatively, players can head through the sewers as they are no longer blocked. Go to Elena and give her the distillator.

Delivering the Samples
Elena will extract a sample of the plague, but the results of her test are strange. In order to get refined results, she needs requires help from her mentor Guidor in Varrock. Elena will hand you a plague sample, along with liquid honey, sulphuric broline, and ethenea. She will also request that you visit the Chemist in Rimmington to obtain some touch paper to bring to Guidor. You MUST have the plague sample in your inventory for the chemist to give you the touch paper.

If any of the samples break, players can get them replaced by talking to Elena. It might be wise to use the drop trick to get a second set from Elena. The extra set can be banked, preventing the need for a trip back to Ardougne in case of an accident.

The plague sample is extremely fragile. Use of any of the following will cause the sample to break:
 * Any combat
 * Teleport spells and tablets
 * Teleportation jewellery
 * Spirit trees
 * Failing agility shortcuts

Use of any of the following will NOT cause the sample to break:
 * Charter ships
 * Fairy rings -unconfirmed
 * Balloon transport system
 * Canoes
 * Keldagrim carts

Some of the methods that can be used to transport the materials are:
 * Another easy method to accomplish this step is to walk/run to East Ardougne docks and take the boat to Brimhaven (30 coins, or if you have earned your Karamja Gloves - 15 coins); on the same dock you arrive at there is a charter service. Take the charter service boat (at a charge of 1,600 coins) to Port Sarim, east of Rimmington.

Foresight
''While talking to the chemist, do NOT mention the plague sample or else he will take it away, and you'd have to start all over again. You do, however, need to have the plague sample and all three vials in your inventory when you talk to him to access the dialogue involving Elena.''

Tell him that you are Elena's friend and that she needs some touch paper for Guidor. On hearing her name, the chemist hands you over some touch paper, no questions asked. However due to the nature of the sample, Varrock has instituted a guard to do spot checks. This prevents you from bringing the three vials of test liquid to Guidor as they will be confiscated. The chemist will suggest giving a vial to each of his three helpers: Chancy, Da Vinci, and Hops. They are located right outside the chemist's house crowding around a fire.

Make sure to give the bottles to the right people or you will not receive them when you get to Varrock.

Give Chancy the liquid honey, Da Vinci the ethenea, and Hops the sulphuric broline. Once you have given the vials, they will tell you to meet at the Dancing Donkey Inn in Varrock.

So Far, So Good
The samples and paper need to be taken to Elena's mentor, Guidor, in Varrock.

''Once again, DO NOT teleport to Varrock by any method possible, as the Plague Sample will break and you will have to get a new one. Though you can again bank the items and teleport, take the items from the bank and then proceed through the rest of the quest.''

You must however, give the vials to the three in front of the chemists' house before proceeding, as you won't be able to gain entry to the caged-off area while in possession of them.

Also, if you happen to give one the helpers the wrong sample and wish to save the extra trip required to fix your error, you may drop the samples outside the gate before speaking to the guard, enter, and telegrab them from the other side.

Before you head there, buy both parts of the Priest gown from Thessalia's Fine Clothes located on the west side of Varrock Square for a total of 10 coins.

Next, go to the south-east part of Varrock where one guard stands in front of a gate. Try to use the gate; the guard will search you, but he won't find anything conclusive. Use the gate again, and you will be allowed to pass. Head to the Dancing Donkey Inn and talk to the chemist's assistants to get the vials back. ''Your inventory MUST have space for the three vials. Having a full inventory will require you to obtain a new set from Elena.''

Secrets
Head to Guidor's house in the south-east corner of the gated area. When attempting to enter, Guidor's wife will say that she is waiting for a priest to come and bless Guidor. Equip your priest gown and she will let you in. Talk to Guidor, who says that his wife has kept him under house arrest because of the rumour about the 'plague-carrier'. Give him the vials and sample and tell him that Elena has sent a sample that needs to be processed. After analysing it, he will come to a surprising conclusion. He tells you that the plague is just a lie and the real question is why.

Return to Ardougne and talk to Elena. When you tell her that Guidor found nothing in his results, she suggests that this must be a hoax and that you should speak to the person on top of this - King Lathas. The king is located in his bedroom on the 2nd floor of the Ardougne castle, just south of Elena's house.

When told that the plague is in fact a hoax, the king replies that he did it for the best of his people, and that it protects them from a "far greater danger". He then tells the player about the journey of King Tyras - the King of West Ardougne and King Lathas's brother - towards the west and that he has been corrupted by drinking from the Chalice of Eternity. Hence, the wall has been erected between the cities to protect East Ardougne and in turn, all of Runescape.

Rewards

 * 3 Quest points
 * 1,250 experience
 * Use of the Combat Training Camp north of the city.
 * Ability to travel freely through the West Ardougne gate.

Trivia

 * Da Vinci is a reference to the famous multi-talented Italian, Leonardo Da Vinci.
 * The name of the man who helps you get over the wall, Jerico, could be a reference to the old bible story about Jericho's wall.