Umamusume: Pretty Derby

Horse-girl racing idol sim sounds like a joke, but Umamusume's training loop is surprisingly sharp, races are tense, and the production value combined with attention to detail in recreating aspects of real world Japanese racehorses is weirdly elite. Gacha is generous upfront, but obviously brutal long-term. You'll probably resent how much fun it is. A global phenomenon for a reason: addictive, unskippable, potentially shameful.