Don’t understand the point of the game

I don’t really play video games usually only card games but my friend told me to get this n said it’s like slay the spire which I sucked at for a while. I just finished the final ante on my first run and is that the end of the game? It took like 30 mins and I was expecting it to be a lot harder I beat the 8th ante boss on the first hand. Are there any secret levels or anything not including the endless mode option?