80s glam-rock techno-punk Amazons in Space!
But, seriously, House Escher is one of the six Hive City Houses of Necromunda, making it one of the six original playable factions for the game when it was debuted.
House Escher's "gimmick" is that it is a matriarchal House; some unknown, inexplicable genetic quirk results in the females of House Escher being born strong and hearty, but males are invariably stillborn, mentally handicapped or physically disabled, forcing the House to rely on its womenfolk to handle all of the various tasks of running a House. The Escher have risen to this task with pride and skill, and have held their place in the wars of the Houses for countless generations. Indeed, they have come to view the menfolk of other Houses with varying levels of pity, amusement or disdain, viewing them as often being little better than their own wastrel, sub-human male-spawn. This gives them a long-lasting and mutual enmity with House Goliath, whose entire culture is bound up in excessive displays of masculinity and machismo; House Escher thinks of them as ridiculous, swaggering, musclebound idiots. The relaunch, for the most part, stayed faithful to this while also giving them the role of masters in the production of chemicals, drugs, and other pharmaceutical wares.
This same edition also gave them a status boost; whereas the first issue of Necromunda had used House Orlock and House Goliath as its default/starter gangs, the relaunch instead uses Houses Goliath and Escher, to better provide a contrast in sides, per the developers' own words.
In the distant past, before Necromunda was named as such, there were three sisters: Celestria, Sydrena and Solarana. These three sisters were legendary warriors, having felled countless foes and pledge loyalty to the future planetary governor Martek Hel'mayr. Eventually they would set up cloning vats and combine their genetics in order to begin the bloodline of House Ulandari.
At some point, House Ulandari would split, with Ulantri retaining all the posh nobles, while the upstarts and daredevils broke off and formed their own house, House Athenos, and gained control of the chem trade. While the renamed House Ulanti gained prominence following assisting Cinderak Helmawr become planetary governor, Athenos suffers serious losses due to internal strife and attrition. Some members of Ulanti found themselves disillusioned with the decadence that strayed so far from their forebears and became House Eschaki, absorbing the collapsing House Athenos.
Eschaki, being a new house during a period where other, more established houses were expanding, were facing an uphill battle to dominance. Among these was House Goliath, who unlike their modern iteration were merely a bunch of swole forge-bros. These houses would war for a good while until a point where Eschaki just decided to both poison the Goliath's food supply and butcher their numbers with a bunch of gene-modded drugged-up loons, spelling doom. For whom? Well, technically both; while Goliath was immediately destroyed by the war, Eschaki would suffer the effects of their addictions to gene-mods and drugs as their men would be born with increasingly glaring and crippling defects. This would have been the end if it weren't for a band of women who took the reins of Eschaki and establish the groundwork for the modern matriarchy.
It was here that House Escher as we know it were born today. They specialize in exotic chemicals and bio-agents; tonics, drugs, elixirs, gene-mods and a vast array of other bio-pharmaceutical products. Their Space Amazon status was even directly attributed to genetic degradation from dealing with these concoctions, and their menfolk are now completely out of the picture - while the men they do produce are still hopelessly disabled, they get around this by use bio-pharmaceutical archeotech (with a little help from House Van Saar) to reproduce, with strange drugs that can induce parthenogenesis (asexual, perhaps even homosexual) pregnancy. This makes their eternal rivalry with House Goliath develop a layer of extra irony; Not only was Goliath a result of Escher trying to make new men to replace their defective ones (which went very wrong), but Goliath depends on Escher-produced stimms, gene-tweaks, hormone mods and other bio-chemical products to create and sustain their unnaturally enhanced, augmented physiques.
Their chief allies come in one of three aspects: The Water Guild (who share a good relationship with Escher thanks to their domination of the chem trade), the Cold Trade (those smugglers of verboten and proscribed xenos and xenotech) and House Ulanti (a highly influential noble house whose bloodline shares a common origin with Escher, thus meaning that some noble advisors may come to visit the gang)
Escher also houses Shivvers, usually low-level psykers who act as soothsayers and oracles. Gangers both inside and outside the house value the counsel of the shivvers and will seek their aid in order to hear prophecies and attempt to curse their enemies. Most notorious of them all is Lord Helmawr himself, and Escher has taken it upon themselves to protect the shivvers from the lord's grasp.
Back when House Eschaki was around, they discovered a dreadful chemical process in which they were able to reanimate the remains of a recently slain warrior. The results are quite shocking: The corpse retains their muscle memory and reflexes and they become inured to any pain. The process even turns the maiden's blood into a toxic ichor ideal for coating weapons. In exchange, they lose their ability to heal, as the cocktail of drugs responsible for their undeath destroys their biology. This also has a cost of destroying their minds, as (in game terms) they retain none of their thoughts or memories aside from a furious rage on par with an Eversor.
House Escher's speciality was Agility; it was the one skill table that all of its members could roll on. Escher Gang Leaders were the only ones in the gang who could take Ferocity skills, whilst Escher Heavers were the only ones who could have Muscle skills.
Escher's focus remains on its speed and finesse, hence the availability of Agility, Combat, and Cunning trees to all gang members while their exclusive tree is Finesse. No gang member has access to the Brawn, Shooting, or Savant skills by default due to their reliance on grace above might combined with a preference for poisoned weaponry. Their favored weapons are typically focused on poisoning opponents or weakening them before delivering a coup de grace, like the chem-thrower, the combi-bolter/needler, the stiletto knife, and the shock whip.
The House of Blades supplement released in 2020 gives plenty of new members and tools for Escher to utilize. Most notable among them are the abovementioned Death-maidens. While remarkably more dangerous than a normal champion, she suffers a drastic downgrade in their skill progression as they have access to only a scant few trees. Even worse is that, if you buy a chymist as a hanger-on, they can also attempt to resurrect slain matriarchs and gang queens as Death-maidens at no cost (though they lose absolutely everything else in the process). Their lone Prospects are the Wyld Runners, a bunch of roving bandits/scouts who tend to carry bows and train Phelynxes. Escher also has access to their own pets, chiefly Phyrr-cats and Phelynxes (exotic cat-like xenos) who tend to accompany their masters, but they can also summon the Khimerix, a massive monstrosity of a pet.