I've been playing a lot of Keyforge lately. It's a ccg with the twist that there's no deck building because all decks are premade, and randomly generated by an algorithm. What I love about this format is that it forces you to play with cards that are more situational or not perceived as the most powerful. While deckbuilding should in theory allow for a great diversity of decklists, what often happens in practice in games like Magic or Pokemon is that players will end up building decks that fall into one of a handful of very similar archetypes, as players all end up including the same very powerful cards and ignoring the majority of cards that don't fall within the higher tiers of the current meta.
This format also makes it very easy to pick up, since you don't need to purchase single cards to craft a competitive deck.
There's also a pretty good online implementation that's free to use and alot of fun at
https://www.thecrucible.online/. If anyone would ever want to play a game online or learn more about the game in general, let me know!