Pyroforming is a planetscaping method similar to Terraforming. While Terraforming is the process of making an inhospitable planet habitable for oxygen breathers, pyroforming is a similar process which transforms the conditions on a planet to those more friendly to species like the Pyrians. Pyrians use pyroforming to help spread their empire by pyroforming entire planets so that they can move in and populate them. It is a necessary technology for Pyrians, because planets with the desirable type of atmosphere are uncommon, so in order to spread they need to be able to consistently create colonies that are within several lightyears so that economies and government can be maintained.
Pyroforming also has military uses, as pyroforming generators can be put onto inhabited planets and used to make the inhospitable, either killing the peoples on the planet, or forcing them to move away.
About 12 pyroforming generators are needed to successfully pyroform a planet such as Samsarra.