Mycetic Spore
Mycetic Spores are the Tyranids' equivalent of Drop Pods with Ripper Tentacles. They could carry Carnifexes. Just think about that for a second. Deepstriking Carnifexes. That's awesome, right? Apparently Games Workshop didn't think so, because they removed the Mycetic spores from the 6th edition codex (or as it shall henceforth be known, "Nerf and the world Nerfs with you"). The reasons why GW did this are discussed further below, but as it stands the Mycetic Spore has been retconned/replaced by the Tyrannocyte. There's also Microscopic Mycetic Spores, used to blanket a planet and help assimiliate bio materials during the final stages.
The ChapterHouse Fiasco[edit]
Before 4th edition at the earliest, there was a company called ChapterHouse Studios, who was responsible for making a whole ton of supplementary 40K stuff that GW was too fucking lazy to provide, like conversion kits for Tervigons, shoulder pads for popular but less supported Space Marine Chapters, and these babies: actual Mycetic Spore models. GeeDubs, being the greedy fucktards they are, got jealous that someone was trying to actually make things without having to go to to them for even more wallet milking. To this end, in 2010 they decided to sue Chapter House for copying things they made.
In a shocking turn of events (shocking in that, bad as GeeDubs is, Chapter House was actually guilty with stuff like "Pre-Heresy Terminators"), Chapter House actually won the lawsuit, as GW was trying to sue for things they never made or depicted in art, and thus owned no rights to.
For a while, GW let sleeping dogs lie, being unable to actually sue for things they never made, and being too lazy to try making their own spore pods. However, by 6th Edition GW had removed Mycetic Spores from the Tyranid Codex. With them went the ability to actually get Zoanthropes anywhere reliably and the aforementioned Fex-Striking. However, GW never quite gave up their legal game, and the final death knell finally rang in 2014, as GeeDubs convinced a court to freeze all of CHS' assets, thus ending the production of these spore pods and all other disputed assets. Although CHS reopened briefly after this, as of this writing in 2021 their website appears to be quite, quite dead.
Good job crushing the little guy, GW, you giant turdnugget.
Still, if there is one good thing that's come of this, it's that GW has *finally* gotten off their ass and started to close major gaps in their miniature lines. We're talking about gaps that have languished unaddressed for decades, up to and including releasing entire factions that had previously only been mentioned in fluff or in a handful of drawings from sourcebook art. Truly, we are living in a new era.