House Mirraflex was originally a minor-but-ancient Oldblood House, which became a ruthless military ruling House during the War. House Mirraflex considered itself the inheritor of the Homeworld's culture — it was xenophobic and frequently refused to work with Newblood Houses like House Xianthellipse, which it saw as an infiltration of the Homeworld tainted by lesser species biodata.
House Mirraflex was founded as an esoteric martial lodge by General Mirraflex, a noted leader in the Yssgaroth campaigns. According to the House, he had foreseen a coming second War — but every House claimed to have some special insight, so it was not particularly likely.
In the thousand years immediately preceding the War, when "mutations" started to be produced by the Houses' breeding engines, Mirraflex had far more eccentric (even psychotic) members than the other Houses. This was only overlooked because Mirraflex tended to use its eccentricities to defend the Protocols.
During the War, Mirraflex became one of the foremost Houses and the one most efficiently and ruthlessly dedicated to the War effort, frequently interfering in the Spiral Politic. When one world looked as if it might have a civilisation which would take a "sceptically neutral" position on the War, Mirraflex removed the entire star system from history. This created Spancil's Hypothalamus, an anomalous nebula. In another incident, a member of House Mirraflex lived as the repeatedly-dying messiah of a posthuman rebirth cult for centuries just to prime the civilisation to be drafted into the War as regen-inf troops. The thousands of young adults who committed ritual suicide were considered collateral damage. (PROSE: House Mirraflex) After Chris Cwej became annoyingly sulky at the body he was given, Mirraflex wanted to have him killed outright. (PROSE: Christopher Rodonanté Cwej)