Dominion, Slay the Spire, or other deck building games

I’m looking to add a deck building game to my collection. I’ve mainly heard of Dominion and the recent Slay the Spire game. Maybe there are others out there.

I don’t want to have to buy expansions for Dominion, as I’m aware there are a lot. What’s going to have the most longevity with just the base game? Thoughts on deck building board games in general? Thank you.