Hello, I am an indie developer who wants to develop games. I have conceived the concepts, frameworks, and elements of the games I want to make, but I am writing this post because I want to study and learn about the fun part. If a game is novel or whatever, the most important thing is that it's fundamentally fun. Otherwise, it's not a game (play). Instead of copying rules or elements, I want to research what the essence of a game is and what the essence of fun is by looking at games that you all enjoyed. Please recommend one game in the comments that you enjoyed playing up to the mid-2000s, whether it's an arcade game, console game, or computer game. You can just leave the name. I would appreciate your recommendations.
Reason for asking for game recommendations from others: I think it's important to analyze games that are commonly enjoyed by others rather than my own subjectivity.
Purpose: To strengthen the most important fun in games and make players feel entertained, by analyzing and referencing game fun theory books and related documents. I am also personally curious.