You guys remember watching a show that's not particularly good but isn't so offensively bad, so you won't see people talking about them unless you bring the topic out?
One thing I remember.
(the show based on the card game, not the Danish card game itself)
It left me an impression because it, well, kinda panders to my interests (hint: avatar). It came out when a bunch of European-based card games were suddenly a thing and shows based on them were plentiful.
It wasn't bad but it leaves little to memory. With that said, despite being your average "cartoon based on card game", it was pretty decent and unique for what it was. To start, It had none of the "card games are serious business" stuff a lot of similar shows have - it literally is just playing for fun. The "serious business" side had nothing to do with cards but instead is about an alternate dimension where the cards were based from - so while you have humans playing with creatures in some holodeck-like machine, there is an actual political warfare in the parallel universe.
And speaking of which, I find how they handled their play time unique. Apparently the people who play in the cartoon receive some touchscreen device which stores card data, and whenever they want to play they simply access it. They then travel to a hub of sorts, all while leaving their "physical" body in the real world. It's weird.
The characters themselves are okay. The humans are your typical card game characters though I find it nice that the girl of the group likes the bug-themed deck. The creatures themselves are fun.
With that said the first season has some shitty flash animation. It got better though and has a decent arc.