https://steamhost.cn/app/948350/Royal_Booty_Quest/

Basically, what happens there is pretty much described in this thread:
https://steamhost.cn/steamcommunity_com/app/948350/discussions/0/1652171126134616862/

Even screenshots from store page contains slightly recolored sprites of cards from StS, with completely copied descriptions. After questions, dev of RBQ has confirmed that his game "feature characters from StS". Im unsure if its legal, but assets theft is 100% not (especially since, if I remember correctly, they werent paid third party assets or something under creative commons, but artworks drawn exclusively for slay the spire)