The main advantage factions besides CHAOS have on the IoM is that they don't have their techs literally religiously opposed to actually understanding the 'hows' and 'whys' of their tech. At some point AM decided to declare the scientific method Political Heriteck. As in your only allowed access to it if you have enough political weight within the local politics of AM. Which is why Avernus is likely doing so well... the high ranking members of AM are more interested in results than in micromanagement by dogma. Remember Avernus is a newly collonized Deathworld and the gravy train of STC and ancient tech is still coming on strong. It'd be a political nightmare to try and stop that train while its still spewing forth glorious things.
If the IoM wasn't going to implode soon, long term I could see Avernus AM actually importing STC fragments just to complete them. Eventually trades are made for STC fragments in exchange for completed ones and occasionally some production. Avernus would end up Atlas' golden cyborg goose. Subcontractor of STCdex that Fortress Deathworld would be. Even better you can banish low level fodder priests to Avernus if they are too inquisitive and everyone will think your punishing them.
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I've been watching a lore mine on youtube called 'Vaults of Terra' and one of the things that really helped out the Orks is that they managed travel the warp regularly while it was all screwed up after the Eldar Empire pokevolved into Slanesh. So if the Warp is completely borked post IoM, the Tau and their shallow Warp skimming with help them spread. They only move through the Warp at 20% of IoM speeds. Which would be comically fast if the Warp is only calm enough sporadically to use in the meantime. 20% speed all the time instead of partial speed some of the time.
Also, there is apparently some evidence that the Etherial cast are psykers... which is why the Greater Good thing works. Also, a few thousand years ago an entire cast of Tau were winged fliers... now they aren't but are all the pilots. Basically, I'm now convince that Tau are actually pokemon and once they evolve bigger souls they will gain the ability to pokevolve. They already have types Etheral (psychic), Fire (fighting), etc... I fully expect that the ral reason the Tau keep throwing mooks at the Dark Eldar is the Etherals are actively trying to get Poison and Dark subtypes and the DE are falling for it.
If the IoM wasn't going to implode soon, long term I could see Avernus AM actually importing STC fragments just to complete them. Eventually trades are made for STC fragments in exchange for completed ones and occasionally some production. Avernus would end up Atlas' golden cyborg goose. Subcontractor of STCdex that Fortress Deathworld would be. Even better you can banish low level fodder priests to Avernus if they are too inquisitive and everyone will think your punishing them.
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I've been watching a lore mine on youtube called 'Vaults of Terra' and one of the things that really helped out the Orks is that they managed travel the warp regularly while it was all screwed up after the Eldar Empire pokevolved into Slanesh. So if the Warp is completely borked post IoM, the Tau and their shallow Warp skimming with help them spread. They only move through the Warp at 20% of IoM speeds. Which would be comically fast if the Warp is only calm enough sporadically to use in the meantime. 20% speed all the time instead of partial speed some of the time.
Also, there is apparently some evidence that the Etherial cast are psykers... which is why the Greater Good thing works. Also, a few thousand years ago an entire cast of Tau were winged fliers... now they aren't but are all the pilots. Basically, I'm now convince that Tau are actually pokemon and once they evolve bigger souls they will gain the ability to pokevolve. They already have types Etheral (psychic), Fire (fighting), etc... I fully expect that the ral reason the Tau keep throwing mooks at the Dark Eldar is the Etherals are actively trying to get Poison and Dark subtypes and the DE are falling for it.