And DE continue to be cool: recent update introduced a mission based partly on community lore and fanfic.
New mission: Man of Few Words. Rescue Darvo K'Teer's friend Clem, a lovable, dumb-as-rocks Grineer clone whose Queens conditioning failed, who likes Tenno and wears a scarf in imitation of syndanas, and loves, just loves, his two Grakata.
Lexicon for non-Warframers:-
Tenno: the game's players play superpowered space ninjas, who wear the eponymous "warframes" (equivalent of classes in other games) - like Iron Man suits but with nanotechnology that melds them more intimately with the Tenno's flesh.
Darvo: a renegade merchant friendly to the Tenno, former Corpus (the big bad megacorp in the solar system).
Grineer: genetically engineered hive soldier clones, who fight for the mysterious "Queens", who are bent on conquering the solar system.
Clem: the Grineer have a language that's vaguely reminiscent of English, one of the things they shout in combat is "Get clem!", "clem" being the Grineer word for "them"; but the community amused itself by imagining that Clem was some sort of person the Grineer are trying to get. Recently there was some fanfic related to this imaginary "Clem", including some cute cartoons. DE ran with it. Perhaps (some cynics say) partly to defuse some rabble rustling that had been developing about the possibility of changing some fundamental mods in the game.
Syndanas: decorative, ceremonial scarf/cloak type things the Tenno wear (fluff bought with f2p currency).
Grakata: a characteristic Grineer full auto weapon.