I checked out Teppen around when it came out and thought it was cool, but didn't get back to it until a few days before the new DMC5 expansion came out. It has since consumed a significant amount of my freetime, and I really dig everything about it. Taking a card game and making it real time like that is a concept I've never seen before, and I dived in deep trying to put together a Dante deck where all the cards synergize together while still having the potential to counter any type of deck. The aesthetics are also super strong, all of the art is great and it cool seeing more realistically detailed depictions of characters that traditionally would have a more cartoony style like X and Morrigan. Music is also top notch, giving some great orchestral remixes of songs that typically use that style, as well as ones like Sky Lagoon from Mega Man X 4 Lock and Load from Devil May Cry, and of course the incredible operatic rendition of Devil Trigger.

If you've got any interest in either card games or Capcom I'd recommend giving it a look, it's free to play but it doesn't seem too aggressive about you needing to spend money to get worthwhile cards. Maybe that changes if you really climb the ranks though (I'm currently in the bottom of C Rank)