Top books on r/gamedesign

The Art of Game Design

Game Mechanics

Designing Games

Theory of Fun for Game Design

Challenges for Game Designers

Level Up! The Guide to Great Video Game Design

Game Feel: A Game Designer's Guide to Virtual Sensation

Rules of Play

Introduction to Game Design, Prototyping, and Development

Characteristics of Games (MIT Press)

Level Up!: The Guide to Great Video Game Design

Game Design Workshop

Game Design Workshop

Glued to Games

The Design of Everyday Things