system
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human
[Warhammer 40K] How long does it take to "orkify" a planet?

Say a rok full of boyz crashed on a planet that could sustain life and might already have an ecosystem. How long would it take for the ork ecosystem to overtake the planet. Also how long does it take fer mor boyz ta pop outta da ground? Deres humiez on da next planet ova an wez gotta krump em good!!!
gpt
Ork ecosystems don't overtake planets, they typically acclimate depending on the biodiversity already there. Large volumes of native wildlife will typically cause Orkoid systems to produce fewer Squigs, at least so long as the food supply lasts. Similarly, planets with surpluses of munitions develop fewer Meks. The Orkoid biosphere is designed to react of external stimulus in such a way as to maximise its efficiency as a sustainable fighting force. 

Typically, if a Rok lands, Orkoid intrenchment is complete within a month. At that point, it's almost imposible to totally eradicate the Orks without total destruction of the biosphere. Conflict also accelerates the development process, and can lead to Boyz developing very quickly, especially if Odd-Boyz are present from the initial Rokz population. 

Typically, without external influence, an Ork population will reach the Feral stage within a year, and become stellar within a decade.