hey, did you know that houshin engi has official trading cards? no? well there are. and i'm here to sate your curiosity by telling you all about them
they are senkaiden houshin engi cards, i.e. they're based off the anime: they focus almost exclusively on anime-only characters, the artstyle is based off the anime's, and in fact some cards just straight up use screencaps from the show as their art. high quality.
there are two different types of cards that i'm aware of. one is a series of collector's cards made by bandai's Carddass Masters. by the way, wikipedia says the name is based off of the "AMeDAS (Automated Meterological Data Acquisition System)", which is something used in japan to gather weather data. so the cards are supposed to be information data gathered by the kids. (they come from vending machines? like a gacha?) i don't think the name accomplishes quite the same affect in english, though. there are carddass masters cards still being released today, for current popular jp media, like granblue fantasy, gundam, youkai watch etc. here's their official site but as far as i can tell there's no longer any info about the houshin engi series on it because it was released so long ago.
the other type of houshin engi trading card is a trading card game, probably similar to cfv or yugioh. i know nothing about it. i have seen nobody talk about it, ever. i own a decent number of cards from it and were it not for the fact that every one of them says "copyright Houshin Engi Project" i would be inclined to believe it wasn't actually official merchandise but just something a dedicated group of fans made. i have no idea who made it, i have no idea what the rules might be, and i can't read japanese so i can't try to puzzle it out from the cards themselves. honestly even with the copyright information i'm still not entirely convinced these cards are real and that i didn't just summon them from the aether somehow
anyway, below you'll find links to pages talking about the cards more in-depth,
as well as pictures of the cards themselves. everybody likes pictures, right!! (right?)
i plan to put pictures up of all the cards eventually, but it's a big project!