This is my personal favorite deckbuilder, mostly because you have much more control over your deck than in something like StS. Feels more like a roguelike version of an LCG or TCG to me that way, which aligns with my tastes.
The dev is also very active and has been supporting the game for years.

The most relaxing thing you can find on Steam. Perfect for zoning out after a long day. And it's free.