Board Thread:Warhammer 40k General Discussion/@comment-25618639-20150426193759/@comment-25177957-20150430185936

There's a huge problem with ranking the Tyranids as Type 1, a type 1 civilization only has the energy's worth of a star, and access the renwable energy, the Tyranids have that. Then a Type 2 civilization can construct megastructures in space used for gathering energy (Tyranid hive fleets might be an example). Finally a Type 3 civilization might have the resources avalible to, or has already gathered the energy of an entire galaxy, since 40k lore assumes the Tyranids have already sucked the biomass out of an entire galaxy before the Milky Way. Tyranids only use one source of energy, which is Biomass, but it's essentially the only source of energy they need, and there's plenty of it throughout the universe. Also, about Chaos, warp energy is essentially infinite, as well as emotional energy, Chaos itself isn't exactly a civilization, but for the sake of ranking them, we will count it as one, after all, the Astartes at the time of the Great Crusade assumed things such as Chaos Daemons were just strange aliens.

Even sources describing the Kardashev Scale note that it might not be good at all for ranking alien civilizations since their methods are unpredictable, so considering all of the xenos of 40k, a custom scale would be needed.