There are 27 character cards in the new Genius Invokation TCG in Genshin Impact. That should give you enough variations in decks to use in battles all over Teyvat.

This game was teased way over in update 2.6 when Itto mentioned it. While it seemed a one-off mention, it became real when 3.0 rolled by and was released

Genshin Impact Genius Invokation is perhaps the most ambitious addition to the 3.3 update later this year. It’s a trading card game on PC that lives within the ultra-popular free…

Introducing Genius Invokation TCG, the card game that's been taking Teyvat by storm! But let's not get ahead of ourselves. It's time to head to The Cat's Tail, and listen…