Thermonuclear smoke devil

This article has a strategy guide.

All information on mechanics and strategy will be on this page.

This article has a Slayer task guide here.

Information comparing locations for Slayer tasks will be on this page.

Thermonuclear smoke devil



Released		10 April 2014 (Update)
Members		Yes
Combat level		301
Size		4x4
Examine		Woah.
League region		Kandarin✓

Combat info

XP bonus		+0%
Max hit		8
Aggressive		No
Poisonous		No
Attack style		Magical ranged (100% prayer penetration)
Attack speed		2 ticks (1.2 seconds)
Respawn time		15 ticks (9 seconds)

Slayer info

Slayer level		93
Slayer XP		240 xp
Category		Bosses, Smoke Devils
Assigned by

Combat stats


240	230	220	360	1	310

Aggressive stats


+0	+0	+0	+0	+0	+0

Melee defence


+11		+4		+9

Magic defence


+800			20% weakness

Ranged defence


+900		+900		+900

Immunities

Poison		100% resistance
Venom		100% resistance
Cannons		Not immune
Thralls		Not immune
Burn		Not immune

Open in DPS calculator
Advanced data

Monster ID		499
Link		MOID

The thermonuclear smoke devil, often referred to as thermy, is the boss version of the smoke devil. It requires a minimum of 93 Slayer to damage. Located at the Smoke Devil Dungeon south of Castle Wars, the Thermonuclear smoke devil can only be attacked on a smoke devil task, with the exception of one kill for the Western Provinces Diary (provided that the player has 93 Slayer without boosting).

It is the only monster to drop the smoke battlestaff, jar of smoke, and the pet smoke devil. It drops the occult necklace at a higher rate than smoke devils.

Unlike most NPCs, the Thermonuclear smoke devil is always able to walk through other monsters/players. This is to prevent players from safespotting the boss using the smoke devils found in its lair.

A dwarf multicannon cannot be used inside the boss room. If it is set up, the cannon will be destroyed.

Location

There are several ways to access the dungeon:

The fairy ring code BKP will bring the players just south-west of the dungeon.
Using a ring of dueling to teleport to Castle Wars, then running south-west.

Location	Levels	Members	Spawns	Map	League region
Smoke Devil Dungeon	301		1	Show map	Kandarin✓

Money making

The following money making guide is available for Thermonuclear smoke devil:

Method	Hourly profit	Skills
Killing the Thermonuclear smoke devil	1,695,911	93+ required 90+ , 94+

Drops

Drop rates are estimated based on 8,743,517 samples from the Drop Rate Project, unless otherwise cited.

The average Thermonuclear smoke devil kill is worth 24,449.46.

The average Thermonuclear smoke devil kill while on a Konar task is worth 26,233.94.

100%

	Item	Quantity	Rarity	Price	High Alch
	Ashes	1	Always	39	1

Pre-roll

Item	Quantity	Rarity	Price	High Alch
Occult necklace	1	1/350^[1]	319,573	27,000
Smoke battlestaff	1	1/512^[1]	1,746,834	9,300
Dragon chainbody	1	1/2,000^[1]	182,499	150,000

Weapons and armour

Item	Quantity	Rarity	Price	High Alch
Rune dagger	1	5/107	4,568	4,800
Rune chainbody	1	4/107	29,611	30,000
Red d'hide body	1	3/107	5,755	6,738
Rune battleaxe	1	3/107	24,639	24,960
Mystic air staff	1	3/107	24,809	25,500
Mystic fire staff	1	3/107	24,785	25,500
Rune scimitar	1	2/107	15,044	15,360
Rune knife(p++)	50	1/107	7,800	4,950
Dragon scimitar	1	1/107	59,466	60,000
Ancient staff	1	1/107	60,687	60,000

Runes and ammunition

Item	Quantity	Rarity	Price	High Alch
Smoke rune	100	10/107	6,500	1,200
Air rune	300	8/107	1,500	600
Soul rune	100	8/107	38,000	18,000
Rune arrow	100	2/107	4,700	24,000

Consumables

Item	Quantity	Rarity	Price	High Alch
Ugthanki kebab	3	1/107	2,085	36
Tuna potato	3	3/107	4,407	201
Sanfew serum(4)	2	3/107	37,104	360
Prayer potion(4)	2	1/107	18,330	228

Resources

Item	Quantity	Rarity	Price	High Alch
Pure essence	300 (noted)	2/107	600	600
Molten glass	100 (noted)	2/107	8,300	100
Mithril bar	20 (noted)	2/107	19,180	3,600
Magic logs	20 (noted)	2/107	15,280	3,840
Gold ore	200 (noted)	2/107	28,800	18,000
Diamond	10 (noted)	1/107	16,510	12,000
Raw shark	30 (noted)	5/856	21,540	3,060
Shark lure	60	3/856	17,460	360

Other

Item	Quantity	Rarity	Price	High Alch
Coins	10,000–19,999	15/107	10,000–19,999	10,000–19,999
Tinderbox	1	1/107	98	0
Fire talisman	1	1/107	4,550	2
Goat horn	50 (noted)	2/107	2,000	350
Grimy toadflax	15 (noted)	2/107	28,485	165
Onyx bolt tips	12	2/107	96,936	7,200
Snapdragon seed	2	2/107	87,546	72
Ranarr seed	2	2/107	56,056	60
Grapes	100 (noted)	1/107	6,400	0
Magic seed	1	1/107^[1]	69,558	253
Dragonstone ring	1	1/107	10,263	10,575
Crystal key	1	1/107^[2]	20,319	90

Gem drop table

There is a 2/107 chance of rolling the gem drop table.

Item	Quantity	Rarity	Price	High Alch
Nothing	N/A	1/107.2; Never^{[d 1]}	N/A	N/A
Uncut sapphire	1	1/214; 1/108.67^{[d 2]}	228	15
Uncut emerald	1	1/428; 1/217.34^{[d 2]}	473	30
Uncut ruby	1	1/856; 1/434.69^{[d 2]}	1,087	60
Nature talisman	1	1/2,282.67; 1/1,159.17^{[d 2]}	268	2
Uncut diamond	1	1/3,424; 1/1,738.75^{[d 2]}	2,439	120
Rune javelin	5	1/6,848; 1/3,477.5^{[d 2]}	675	1,200
Loop half of key	1	1/6,848; 1/3,477.5^{[d 2]}	9,756	60
Tooth half of key	1	1/6,848; 1/3,477.5^{[d 2]}	9,887	60
Rune spear	1	1/109,568; 1/6,520.31^{[d 2]}^{[d 3]}	11,599	12,480
Shield left half	1	1/219,136; 1/13,040.62^{[d 2]}^{[d 3]}	65,355	66,000
Dragon spear	1	1/292,181.33; 1/17,387.5^{[d 2]}^{[d 3]}	38,438	37,440

^ The "nothing" drop is removed while wearing a ring of wealth.
^ ^2.00 ^2.01 ^2.02 ^2.03 ^2.04 ^2.05 ^2.06 ^2.07 ^2.08 ^2.09 ^2.10 The drop rate is increased while wearing a ring of wealth due to the "nothing" drop being removed.
^ ^3.0 ^3.1 ^3.2 Only dropped if Legends' Quest has been finished; if not, a talisman is dropped instead.

Tertiary

Item	Quantity	Rarity	Price	High Alch
Brimstone key	1	1/48^{[d 1]}	Not sold	N/A
Clue scroll (hard)	1	1/96^{[d 2]}^{[d 3]}^[3]	Not sold	12
Clue scroll (elite)	1	1/500^{[d 4]}^{[d 3]}^[1]	Not sold	12
Jar of smoke	1	1/2,000	90,563	1
Pet smoke devil	1	1/3,000^[4]	Not sold	N/A

^ Brimstone keys are only dropped if killed on a Slayer task given by Konar quo Maten.
^ The hard clue scroll drop rate increases to 1/91 after unlocking the hard Combat Achievements rewards tier.
^ ^3.0 ^3.1 Clue scrolls will drop as scroll boxes after the completion of X Marks the Spot.
^ The elite clue scroll drop rate increases to 1/475 after unlocking the elite Combat Achievements rewards tier.

Dialogue

This article on an NPC has an associated transcript list.
Click here for a list of transcripts that this NPC speaks in.

Combat Achievements

There are 3 Combat Achievement tasks (totalling 12 points) available for Thermonuclear Smoke Devil.

Name	Description	Type	Tier	Comp%
Thermonuclear Veteran	Kill the Thermonuclear Smoke Devil 20 times.	Kill Count	Elite (4 pts)	19.7%
Spec'd Out	Kill the Thermonuclear Smoke Devil using only special attacks.	Restriction	Elite (4 pts)	12.1%
Hazard Prevention	Kill the Thermonuclear Smoke Devil without it hitting anyone.	Perfection	Elite (4 pts)	13%

Changes

Date	Changes
14 January 2026 (Update)	Reverted an efficiency improvement from the previous week's update that caused the thermonuclear smoke devil to behave incorrectly in certain scenarios.
25 June 2025 (Update)	The thermonuclear smoke devil now has a 20% elemental weakness to wind spells. The 1/107 bullseye lantern drop was replaced with a 5/856 drop of 30 noted raw sharks and a 3/856 drop of 60 shark lures. The amount of soul runes dropped was increased from 60 to 100. The 2/107 drop of 150 noted coal was replaced with 2 ranarr seeds.
17 March 2021 (Update \| poll)	Added the Jar of Smoke to the tertiary drop table Reduced the chance of dropping Tinderboxes, Bullseye Lanterns, Pure Essence and Kebabs.
27 September 2018 (Update \| poll)	The boss was given a graphical update to be more distinguishable from their regular variant.
25 June 2015 (Update \| poll)	Added a 'peek' option to the entrance of this boss, allowing players to see the number of other players currently in the boss room.
19 March 2015 (Update)	You can no longer kill Thermy without a slayer assignment if you haven't started the Western Achievement Diary.
17 July 2014 (Update \| poll)	Players can now receive a pet version of this boss after defeating it.
22 May 2014 (Update \| poll)	When Thermy drops a clue scroll, it now appears at the correct place on the ground. Thermy now has an 'Attack' option, rather than 'Fight'. Players can now permanently dismiss the warning that is shown before entering the Thermy boss room.

Gallery (historical)


10 April 2014 – 27 September 2018	27 September 2018 – present

Trivia

A player transformed into a Thermy snowman.

The thermonuclear smoke devil was graphically updated on 27 September 2018 as part of an update. Prior to the update, it was simply a larger version of the smoke devils scattered across the dungeon.
The thermonuclear smoke devil and the Kraken are the only slayer bosses that can be fought with another player.
Attempting to attack the thermonuclear smoke devil with a boosted Slayer level of at least 93 will yield the message: Although Brieve will allow you to kill this boss off-task for the Achievement Diary, the level 93 requirement still applies. Stat-boosts are not accepted.
Players can transform into a Thermy snowman by using a snowman ring, which resembles the thermonuclear smoke devil.
The thermonuclear smoke devil has an eye and not a mouth, as confirmed in a Postbag from the Hedge letter ^[5]

References

^ ^1.0 ^1.1 ^1.2 ^1.3 ^1.4 Envision. "Drop Rates V2." 29 July 2014. Old School RuneScape Forums.
^ Jagex. Mod Ash's Twitter account. 9 March 2016. Archived from the original on 25 March 2019. Mod Ash: "1/128. I hope you got some other decent stuff while that was going on."
^ Jagex. The Kebos Lowlands. 10 January 2019. Archived from the original on 15 March 2019.
^ Jagex. Mod JohnC's Twitter account. 15 September 2014. Archived from the original on 15 September 2014. Mod JohnC: "Kraken, Thermy & Penance Queen pet drop rates - DKS for the final reveal next week!"
^ "Gielinor Gazette - May 2022". Old School RuneScape News. Jagex. 31 May 2022. Archived from the original.

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Bosses

World bosses

	The Hueycoatl Scurrius Giant Mole Deranged archaeologist Sarachnis Kalphite Queen Corporeal Beast Gemstone Crab
The Barrows Brothers	Ahrim the Blighted Karil the Tainted Dharok the Wretched Guthan the Infested Torag the Corrupted Verac the Defiled
The Dagannoth Kings	Dagannoth Prime Dagannoth Rex Dagannoth Supreme
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Moons of Peril	Eclipse Moon Blue Moon Blood Moon
The Wilderness bosses	Revenant maledictus Chaos Fanatic Crazy archaeologist Scorpia King Black Dragon Chaos Elemental Vet'ion (Calvar'ion) Venenatis (Spindel) Callisto (Artio)

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The Forgotten Four	The Leviathan The Whisperer Vardorvis Duke Sucellus

Slayer bosses

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Skilling bosses

Raids

Chambers of Xeric	Tekton Vanguard Vespula Vasa Nistirio Muttadile Great Olm
Theatre of Blood	The Maiden of Sugadinti Pestilent Bloat Nylocas Vasilias Sotetseg Xarpus Verzik Vitur
Tombs of Amascut	Akkha Ba-Ba Kephri Zebak Tumeken's Warden Elidinis' Warden

Source site	Old School RuneScape Wiki
Canonical source	Thermonuclear smoke devil
Content license	CC BY-NC-SA 3.0
License status	declared
Picture	Thermonuclear smoke devil · file details