For his tactics in Gnomeregan, see Mekgineer Thermaplugg (tactics).
MobSicco Thermaplugg
Image of Sicco Thermaplugg
Title Mekgineer
Gender Male
Race Leper gnome (Humanoid)
Class Engineer, Tinker
Reaction Alliance Horde
Affiliation(s) Himself
Former affiliation(s) Gnomeregan
Occupation Self-styled "King of Gnomeregan", Inventor
Former occupation(s) Advisor of High Tinker Gelbin Mekkatorque
Location Various
Status Deceased (lore)[1]
Killable (WoW)

“Explosions! MORE explosions! I got to have more explosions!”

— Sicco Thermaplugg

Sicco Thermaplugg was once a proud and ambitious gnomish engineer who sought to make Gnomeregan a great and powerful nation. For many years he served as chief advisor to his closest friend High Tinker Gelbin Mekkatorque. His greedy desire for power combined with a lust for revenge against those he felt had cheated him from his rightful place in gnomish society turned him into the greatest traitor of Gnomeregan. When the troggs invaded Gnomeregan, Thermaplugg proposed filling the city with radiation in order to kill the invaders. However, the radiation also killed many gnomes and turned many more, including Thermaplugg, into leper gnomes.

Driven completely mad by the radiation, Thermaplugg declared himself "King of Gnomeregan" and his death was ordered by Mekkatorque. Over the years many Alliance heroes set out to fulfill this task, but Thermaplugg eluded every attempt. In the wake of the Cataclysm, Mekkatorque rallied the gnomes and called upon the other races of the Alliance to join in his full assault on Gnomeregan. The surface was retaken, where New Tinkertown was established, and after a confrontation with Mekkatorque a wounded Theramaplugg was left for dead.


Icon-search-48x48.png This section contains information that needs to be cleaned up. Reason: RPG was too much integrated in his biography; the other subsections and paragraphs need to be made coherent with canon sources.

Early life

Through working the system and gaining favor among the intellectual elite, Thermaplugg eventually won the seat of advisor to the High Tinker. A brooding but imaginative engineer, he served as Mekkatorque's chief advisor for many years, continuing to covet the role of High Tinker.[2]

Cut Short

WoW-novel-logo-16x62.png This section concerns content related to the Warcraft novels, novellas, or short stories.

Thermaplugg's sanity broke during the trogg invasion of Gnomeregan, and he planned on gaining revenge over his friend.

This treason against his people was only worsened when he used trickery and guile to convince the High Tinker to open the flood vents and release the bomb's radiation upon the grand city knowing well the result.[3]

It is rumored that Thermaplugg actually knew of the trogg invasion before it began, and that he ushered in the events that befell the gnomish race. Though those reports were never verified, Mekkatorque believes they could be true.[2] It's currently only speculation, but many believe that Thermaplugg was the mastermind behind the entire trogg invasion.[4]

World of Warcraft

Thermaplugg without his machine.

Mekigneer Thermaplugg rules the fallen city of Gnomeregan from the Tinkers' Court.

WoW Icon update.png This section concerns content related to the original World of Warcraft.

After the irradiation of the majority of the gnomish race, Sicco was branded a traitor and was sentenced to death. He disappeared shortly after the evacuation of the irradiated city. None could say whether or not he still lives within the toxic halls of Gnomeregan.[2] Others gnomes were mutated into leper gnomes and driven mad. They were easily recruited by the jealous Sicco, who himself had been twisted into a leper gnome and rendered insane.[5]

Driven mad by the radiation, Sicco Thermaplugg remained in the former Tinkers' Court carrying out his twisted designs. His obsession for explosives shows for whenever he is threatened, the many bomb machines start up and begin producing explosive protectors, the Bom bots, for their master. Be wary of these machines and deactivate them as soon as Thermaplugg starts them up with a bolt of electricity from his Mechanical Battle-Mount that he is never without.

Sicco retains none of his former pull over the short race, but those who remain in Gnomeregan, driven mad, still follow his lead. Some of the lieutenants and commanders were lost in the catastrophe of Gnomeregan and remain with their machinations of war to aid Thermaplugg.

One fact is certain: he intentionally sabotaged the city so that he could become High Tinker. He now lives permanently within a purpose built mechanical walker which makes him a most terrifying sight to behold, and considers himself to be the High Tinker of the shattered city.

The immense loss of life at Gnomeregan weighed heavy on Mekkatorque's shoulders, and in his fury he ordered the death of Thermaplugg. A band of heroes took up the mission and returned with a tale of victory, but after analyzing the claim, Mekkatorque realized that the mechanized overlord defeated in the depths of the city was likely nothing more than a cleverly engineered facsimile of Thermaplugg.[6]

Operation Gnomeregan

Wrath of the Lich King This section concerns content related to Wrath of the Lich King.

He didn't show his face on the field of battle, but he did send his Brag-Bot to discourage the invaders. He also sent in Commander Boltcog and an enormous trogg. When victory was not in his favor, he revealed an ace: the Irradiator 3000. It looked similar to the bomb that had brought Gnomeregan to its current state but, according to Sicco, was twenty-six times more powerful. Although it was programmed to explode in ten minutes by one of Sicco's agents, he took the machine's remote and reduced the timer down to ten seconds. After this, the High Tinker's forces were forced to retreat back to Tinker Town.

Cut Short

WoW-novel-logo-16x62.png This section concerns content related to the Warcraft novels, novellas, or short stories.

Sicco Thermaplug attempted to trap High Tinkerer Mekkatorque in Sector 17 of Gnomeregan by using Gelbin's old glasses attached to wire to release three troggs into the room. Yet in the end, they were outwitted by the High Tinkerer. The botched trap resulted in Thermaplug being cut in half, losing his legs in the process. Though Thermaplug did survive due to his destroyed battle suit cauterizing his wounds with minimal blood loss. Gelbin decided to leave him for dead so that his suffering would be prolonged, citing it as an appropriate punishment for his crimes against the gnomes. And should he survive, Gelbin couldn't think of anybody he'd rather have leading those troggs than one of their own.[3]


Cataclysm This section concerns content related to Cataclysm.

Razlo Crushcog was sent by Thermaplugg to harass Mekkatorque after the failure of Operation: Gnomeregan.[7][8][9]

It appears that the G-Team, a gnomish organization, finally succeeded in eliminating Sicco with the help of adventurers,[10] as Mathias Shaw mentions that Thermaplugg was miserable and murderous during his lifetime. After being killed, his  [Electromagnetic Gigaflux Reactivator] has been recovered and returned to a safe place in Tinker Town, in Ironforge.[1]

Battle for Azeroth

Battle for Azeroth This section concerns content related to Battle for Azeroth.

Telzo Sparkspanner, another one of Thermaplugg's lieutenant, is the antagonist of the Heritage of Gnomeregan questline.


Shadowlands This section concerns content related to Shadowlands.

 [Mord'al Eveningstar] is a ruthless tormenter of the smallest souls who some say he was known in life as "Thermaplugg".[11]


Notable appearances
Location Level range Health range
Mekgineer Thermaplugg (tactics) 29 27,150
Mekgineer Thermaplugg's Brag-Bot 75 127,600


Main article: Mekgineer Thermaplugg (tactics)#Quotes
Main article: Operation: Gnomeregan#Scripted event

In the RPG

Icon-RPG.png This section contains information from the Warcraft RPG which is considered non-canon.

Thermaplugg in the Monster Guide.

Mekgineer Sicco Thermaplugg was once a brilliant and wise tinker, who despite being incredibly frail even at a young age, was destined to be High Tinker. He cunningly laid the way to the seat, charming people to his side and cranking out one great invention after the next. He worked unceasingly toward his goal, for Thermaplugg planned not only making High Tinker, but also becoming the gnome's first true king in over four hundred years. He envisioned a great kingdom out of Gnomeregan, carved out of the entire western half of Dun Morogh, even if it meant relocating the nearby dwarven communities in the name of progress. Nothing would stop him! However, his closest friend, Gelbin Mekkatorque, ruined all of his goals when the council of tinkers decided that Thermaplugg was too ambitious and chose Mekkatorque instead.[12]

It was his idea that, during the trogg invasion, the gnomes shut themselves from the world. Thermaplugg claimed that the world outside didn't need to be bothered by gnomish problems, for he had an idea that would both destroy the image of Mekkatorque and win him the throne. After weeks of debate, he convinced Mekkatorque to flood the halls of Gnomeregan with radiation via a bomb, thus killing the troggs. If a few gnomes died in the process, he stated, it would be a worthy sacrifice for saving the entire race.[12]

However, due to reasons even Thermaplugg can't remember, he found himself locked inside Gnomeregan when the bomb release began. Despite his age and frailty, he did not die. Some speak that it was his ambition that saved him, while others say he hid and suffered the least of the poison. Despite this, he lived and mutated into a leper gnome. The radiation killed more gnomes than troggs, and many other gnomes in Gnomeregan's walls also suffered from radiation and became leper gnomes. However, in the ensuing chaos, Thermaplugg had begun calling himself a king. To this day he rules over the leper gnomes and continues fighting the troggs. He controls his land with a tyrannical fist, destroying outsiders as rapidly as any other enemy.[12]

He keeps to himself most of his time since becoming king of Gnomeregan, working on insane world-conquering inventions. Thankfully, few if any will ever see the light of day. Paranoid beyond rational thought, Thermaplugg destroys anything that disturbs his work, even his own leper gnome servants. Recently, however, he opened up negotiations with the Dark Iron dwarves, allowing them use of Gnomeregan's tunnels in exchange for a part of Ironforge to call his own. No one knows what may become of this alliance, but it won't be good.[12]

Rumors say that the Dark Iron dwarves and Mekgineer Thermaplugg, head of the leper gnomes in fallen Gnomeregan, seek an alliance.[13][14]

In Hearthstone

Hearthstone This section contains information exclusive to Hearthstone and is considered non-canon.

Thermaplugg appears as a legendary card in the Goblins vs Gnomes expansion for Hearthstone. His flavor text reads: "He was obsessed with explosives until he discovered knitting. Now he yells, “SWEATERS! MORE SWEATERS!”"


  • Thermaplugg was to appear alongside Gnomeregan in a scraped Legionfall Mage Tower challenge for stealth classes called Imminent Launch. He was to be stopped from launching a missile to the Broken Isles. Now allied with the Burning Legion, he would appear in a new armor and ride a fel reaver. This encounter, alongside Gnomeregan's scenario, did not make it out of the PTR for patch 7.2.0.[15][16] Endgineer Omegaplugg may be a leftover from this.
  • It was originally stated that the gnome heritage armor questline in patch 8.2.0 would go into the history of Thermaplugg's remaining family.[17] The questline seen in the final game features nothing of the sort, instead centering on Thermaplugg's lieutenant Telzo Sparkspanner.
  • Sicco Thermaplugg is voiced by Dave Mallow.
  • His first name is presumably a wordplay of sicko, a mentally ill or perverted person, especially one who is sadistic.


Preceded by:
Gelbin Mekkatorque
Ruler of Gnomeregan
Succeeded by: