Biohazard Quest Guide
OSRS Biohazard walkthrough, requirements and rewards
Updated September 2026
Biohazard continues the Elf storyline and unlocks free travel through the West Ardougne gate and the Combat Training Camp. It requires Plague City but no skill levels.
On this page
6 sections
Overview
| Difficulty | Novice |
| Length | Short |
| Quest points | 3 |
| Series | Elf |
| Start point | Talk to Elena in her house in East Ardougne. |
Requirements
Quest Requirements
Other Requirements
- Ability to defeat a level 13 Mourner
Items Needed
- Priest gown top and bottom (obtainable during the quest)
- Gas mask (obtainable during the quest)
Recommended
- Combat level 10+
- Weight-reducing clothing and stamina or energy potions
- Teleports to East Ardougne, Rimmington and Varrock
Walkthrough
Video walkthrough by Slayermusiq1.
- Sneak back into West Ardougne. Talk to Elena, then Jerico south of the northern bank for bird feed, and create a distraction at the watchtower for Omart.
- Retrieve the distillator. Equip the gas mask, climb over the wall with Kilron, poison the mourners' stew, get a medical gown from Nurse Sarah and kill a Mourner for the key.
- Smuggle the vials. Take the plague sample and three vials to the Chemist in Rimmington and give each vial to the right errand boy (Da Vinci, Chancy and Hops).
- Reach Guidor. In a priest gown and with the plague sample and touch paper, pass the Varrock gate, collect the vials from the Dancing Donkey Inn and speak to Guidor.
- Expose the lie. Return to Elena, then confront King Lathas in East Ardougne Castle about the plague being a hoax.
Rewards
- 3 Quest points
- 1,250 Thieving experience
- Use of the Combat Training Camp
- Free travel through the West Ardougne gate
- West Ardougne Teleport in the Arceuus spellbook
Related Quests
Related Tools
Biohazard FAQ
01What do I need for Biohazard?
Completion of Plague City. A gas mask and priest gown can both be obtained for free during the quest.
02Which vial goes to which errand boy?
Give ethenea to Da Vinci, liquid honey to Chancy and sulphuric broline to Hops, so each has nothing worth stealing.
03What are the rewards for Biohazard?
3 Quest points, 1,250 Thieving experience, use of the Combat Training Camp, free travel through the West Ardougne gate and the West Ardougne Teleport spell.
04How long does Biohazard take?
It is a Short Novice quest, though the smuggling section involves a fair amount of running between Ardougne, Rimmington and Varrock.
05Can Biohazard be done at level 3?
It has no skill requirements, so level 3 accounts can complete it, but the level 13 Mourner must be killed carefully as you cannot afford to take damage.
06Is Biohazard worth doing?
Yes. It grants 3 Quest points, opens the West Ardougne gate and is required for the later Elf quests including Underground Pass.
Next Quest
See every quest in the game, or find the next one on the optimal route.
Darren started playing the original RuneScape 2 back in the day and came back when Old School RuneScape launched. He's played on and off over the years and built OSRSToolkit to give players a single place to find reliable tools, calculators, and guides — all informed by real in-game experience.