Skarsnik of the Crooked Moon Tribe is a Night Goblin Warlord most famous for besieging Karak Eight Peaks, Alongside Grom the Paunch, this makes him one of the few goblins to have ever made much of an impact on the Warhammer world.
Followed by the unnaturally belligerent yet loyal Cave Squig Gobbla, Skarsnik is the uncontested ruler of all greenskins within and around Karak Eight Peaks, fighting an endless war against the Dwarfs and the Skaven of Clan Mors to cement his hold over the region.
There is an account of Skarsnik's life, given by the playwright Baron von Bickenstadt, who was captured by Skarsnik's warband and given the choice of writing Skarsnik's biography or being dinner. He chose the former. Skarsnik was born like any other Greenskin born into existence. The goblin that would later be known as Skarsnik started out life by clawing his way out of the dirt, and into the darkness of a glowing mushroom-lit cave, along with the birthing of his brethrens. In time, these small Goblins began to venture into the domains of a Goblin warband called the Backstairs Boys (yes, that is their name), a small tribe that was a faction of the larger Crooked Moon tribe. Even upon his birth, Skarsnik showed an aptitude of intelligence by being able to spurt out his first words moments after birth, helping his fellow goblins rather than climb over them for personal gain and being able to command his brethren through the dangers of the caves. At one point he saved a squig from being eaten by one of his brethren.
When they reached the main base of the Backstairs Boyz, the small Goblins were forcibly integrated into the Tribe as slaves. They were given the task of harvesting the many mushrooms that infest the lairs of the Backstairs Boyz. Skarsnik during this time was known simply as Runt, due to being significantly smaller then the rest of the other Goblins. As years passed, Skarsnik was still a lowly runt in the tribe's slave pens, while his former brethren had since grown up and left him. His small stature, however, did not stop him from rising through the ranks of his tribe. After a few years of personally leading the newer spawnings by himself, Skarsnik was finally elevated to the position as a true member of the tribe, and was renamed as RuntGit, for he still was fairly small. Skarsnik's first claim to fame was a secret edge he used against the other goblins; he gained a powerful ally by freeing Skreekrit Yellowtooth, a Skaven leader and former captive of the Backstairs Boyz. Skreekrit became a Fangleader of Clan Mors and Skarsnik fed him information on Goblins whose interest clashed more directly with his own.
The secretive trade between the Skavens and Skarsnik had made his tribe, and more specifically Skarsnik, incredibly wealthy. However, Skarsnik's personal nemesis, Runtboy Snotruk, found out and revealed Skarsnik's secretive dealings to Big Boss Tarkit. Tarkit ordered for Skarsnik's execution. However, thanks to the timely arrival of a Dwarf expeditionary force attacking the camp of the Backstairs Boyz, Skarsnik was thrown into an underground river and washed up on the outskirts of Karak Eight Peaks. He was found by a marauding warband of Goblin Wolf Riders and taken as a slave. The leader of the Wolf Rider tribe was a grotesquely fat Goblin known by his official title as the Great Grillzer-Griff Makiki da Cunning. Makiki saw potential within Skarsnik, but he wanted to made sure by seeing what Skarsnik might do during his time in captivity. As such, Griff Makiki confined Skarsnik to a small wagon-cage for a few years. During his confinement, Skarsnik studied the habits of the Wolf Rider tribes and hatched a cunning plan that would grab Griff Makiki's attention.
As the Wolf Rider caravan went from place to place within the Badlands, Skarsnik somehow learned the Dwarf language of Khazalid and the human language Reikspiel and instigated a brawl between himself and a Dwarf by implying something sexual between the Dwarf's mother and a mountain pony. The ensuring scuffle got the attention of Griff Makiki, who out found the full extent of Skarsniks cunning demeanor. Impressed with Skarsnik's ability to learn and speak both Reikspeil and Khazalid, the language of the Humans and Dwarfs during his time in captivity, Skarsnik was released from captivity and became a spy for the Griff as a reward. Like in his former tribe, Skarsnik quickly rose through the ranks of the Wolf Goblins, even going as far as to be feared by the other members of the tribes.
Skreech Verminking manipulated Skarsnik into helping in the murder of the Dwarf King Belegar, promising that the Skaven will leave the Hold once the dwarves are dead. Of course, the Verminlord lied and so Skarsnik's army does battle with the Skaven afterwards. During the fighting, Gobbla swallowed a particularly savage Clan Moulder beastmaster whole, only to be fatally cut open from the inside out. Dismayed by the loss of Gobbla, Skarsnik lost heart and abandoned the field. He later found himself leading the Goblins alongside Grimgor's Beast-WAAAGH! He was present at the battle of Middenheim, chasing down the Chaos followers and monsters who fled from the rest of the Incarnates' forces. Skarsnik was killed by the forces of Chaos at this point in an unspecified way before the world was destroyed.
On the Tabletop
Skarsnik has had various stats through various editions.
Like several other worthies, Skarsnik is mentioned during this time, but received no stats in the Orcs & Goblins army book.
Skarsnik is a Night Goblin Warlord who costs 205 points. He sports M4, WS5, BS3, S4, T4, W6, I5, A4 and LD8 for stats, wears light armor, and wields Skarsnik's Prodda (magical halberd, can cast a power level 5 bound spell that is a Magic Missile that inflicts 1 (+ 1 per unit of 10+ orcs or 20+ goblins within 12" of Skarsnik) armor ignoring Strength 6 hit). He and Gobbla fight as a single model with Unit Strength 3, effectively giving Skarsnik 4 more I4 S6 attacks that benefit from Killing Blow. Like all Night Goblins, Skarsnik Fears Elves and Hates Dwarves. His Sneaky Schemes rule lets him attempt to delay units, causing them to enter from their deployment edge in their first turn if he can roll a 6 on a D6 for each of them. His Tricksy Traps rule allows a Night Goblin unit that Flees as a charge reaction to rally, reform and move in the same turn.
Skarsnik's stats don't really change between editions. About the only difference is that Skarsnik's Prodda now does D3 hits when it is fired, which is increased to doing D6 hits instead if Skarsnik is within 12" of a Night Goblin Horde.
In Age of Sigmar
He's currently dead, so to keep the model on sale it was repurposed as a Loonboss with Giant Cave Squig (not to be confused with the Loonboss on Giant Cave Squig). However, the book mentions that the Bad Moon is followed by a smaller sphere of Badrock that smashes shit out of the Moon's way, and generally fights the shit out of celestial bodies. Various ideas on what the orb is include that it might be the Bad Moon's pet squig, the Moon's fist, or, most interestingly, the spirit of an ancient Grot warlord who conquered eight mountains, and in recognition for his kunnin' deeds, the Bad Moon allowed this ancient grot to party with it for all eternity.
Skarsnik in Total War: WARHAMMER