Tyranid Timeline

[Azekai]

So... I know the timeline in 40k can get pretty wibbly-wobbly, but GW seems to have been retconning how and when the Great Devourer became active. I really don't understand how the first genestealer cult of Ghosar Quintus occurs ~600.M41. Given how genestealers reproduce, there should have been more cults. Ymgarl genestealers have been a part of 40k lore for years, but recent accounts puts their discovery only a few hundred years before the appearance of the big hive fleets, hardly enough time to seed billions of monsters across space hulks and the like. According to older sources, Tyranids have been active for thousands of years, maybe more, in unrecognizable forms... which explains the ubiquitous presence of genestealers just fine. The explorators on the planet Tiamet were infected and compromised circa M35. Colossus and the Zoroastra-Attilla wars raged during M39, except that conflict was erased/retconned in favor of Colossus being destroyed in the much more recent Helican Crusade of M41. 

​I don't really care much for this change, for a lot of reasons. I think Geedubs wants to reinforce the '5 minutes to midnight' storyline, but the whole point of the Tyranid threat is that it is an insidious, slow-growing threat. Now it just seems like a dozen plus hivefleets are blindsiding the Imperium overnight, a biological blitzkrieg, if you will. How is Kryptman supposed to figure out that world after world is being eaten after only a couple years? Planets lose contact with the greater Imperium fairly regularlyt.

It makes matters look almost silly rather than dire. 

​tl;dr genestealer cults should be a constant threat, not one that just started popping up yesterday. 

[Malios]

Genestealer cults have always been around as long as genestealers have. Ghosar Quintus was just the first recorded cult raised to the deathwatch's (and Inquisition's) attention.

 

The timeline is always going to be based off pitching a sale: ghosar quintus was the re-launch of the genestealer cults and dedicated deathwatch ranges. Whether we like it or not, sadly, doesn't really matter.

 

The tyranid timeline has expanded quite a bit though over time. 2nd ed it was the coming of Behemoth into Ultramar. 3rd ed it was hive fleet Kraken (and the now official explanation for Iyanden's ghost warriors), fourth ed through 7th it was the envelopment by Leviathan from beneath the gaactic plane as well as hive fleets Gorgon, and Jormungandr.

 

As of 8th edition, the hive fleet timelines (and their behaviours) have been expanded again: ourobouros has been around for thousands of years. Tiamat is new but defending something. Tendrils of Behemoth, Kraken, Leviathan and Jormungandr are more troublesome and the new "big bad" Hive Fleet Hydra.

[Sabadin]

To be fair, the cults being relatively unknown to the Imperium dates back to 2nd edition. There's a part about the Ultramarines arriving to put down the uprising on Ichar IV I believe it was. They are shocked when they discover the stealers, and have no idea what the Patriarch is, other than a terrifyingly powerful psychic xenos. This all occurs shortly before the first reports of Hive Fleet Kraken.

[Closet Skeleton]

The tyranid timeline has expanded quite a bit though over time. 2nd ed it was the coming of Behemoth into Ultramar. 3rd ed it was hive fleet Kraken (and the now official explanation for Iyanden's ghost warriors), fourth ed through 7th it was the envelopment by Leviathan from beneath the gaactic plane as well as hive fleets Gorgon, and Jormungandr.

 

 

Kraken and its near destruction of Iyanden was in the 2nd ed Tyranid codex and a major feature of epic.

 

Leviathan and their potential conflict with Orktarius has a tiny blurb in the 3rd ed codex.

[Lord_Caerolion]

Yeah, my interpretation of the Ghosar Quintus event wasn't that it was the first ever Genestealer Cult, but rather the moment at which the Imperium took notice and began to link them to the Tyranids. Before that, the Imperium just put the uprisings down to "worlds to be invaded by Tyranids display civil unrest".