What are some video games that made you a better gamer?
For example, I am terrible at Super Meat Boy, but just playing it has really improved how I play platformers and games that need faster imputs overall.
World of Warcraft. 12 years of playing and raid/guild leadership helped me learn how to play, not just play. How to:
Theorycraft
Research how to improve
Maximize output and/or efficiency
Take advantage of class synergies in games
Understand the importance of area of effect, burst damage, sustained single-target damage, etc.
Understand damage mitigation vs avoidance, and where each is valuable
Play to my/my team's strengths, rather than simply doing what is "best"
Better recognize trends in game mechanics to anticipate what may come
Recognize the valuable portions of a game's user interface and maximize its visibility while avoiding clutter
I had learned portions of these things in other games, but my leadership role in WoW pushed me to truly understand many things that aren't a major focus in most games.
I have basically the same take from my years of raiding and leading in ESO (still top Argonian DPS babyyyyyyy), and it has also given me an unparalleled intuition when it comes to game and combat design, which comes in handy since I'm a game developer.