This one is a shorty. Be careful when setting the default game state class for custom game modes. Choosing a game state class that extends “GameState” can break your player controller somewhat.
My personal Experience
I was experiencing an issue with my player controller. You might have guessed it, my player controller was not working. Oddly, the tick function was running; but the BeginPlay event was not being called. This messed up a bunch of other things. After a lot of stress, i switched the game state class from “GameState” to “GameStateBase” and it worked.
I really wish unreal had popup notifications for this. Maybe i’ll do a post explaining the differences later when i read up more about it.