Well here's some advice , not really much of an answer.
I really can not figure out why there is no state controller being used for a turn based system. Turn based is all about states. When is who doing what.
Make a control flow for your game.
Somewhat like magic the gathering: (Somewhat similar , this is not exactly the same)
[Draw]
[Upkeep]
[Pre-Attack Main Phase] (spells and
creatures lands > etc)
[Attack Phase] --> Declare attackkers,
defenders instant spells etc Interaction with enemy
[Post-Attack Main Phase] (more spells
creatures lands etc)
[Discard/CleanUp]
Use an enum a bunch of bools any container to keep track of what object is in what state.
If you have a master controller where there is per player per turn instead of all players in one turn (the 2 most common turn based systems) you need to focus on keeping track of pausing when interacting between two objects, without the master controller you need to force control the order in which the events can take place on it self instead rather than also work on global control flow.
Static functions are great sure, untill you acces it when you shouldn't be accessing it. Anybody can call end turn at any time? That takes a lot of accuracy in the control flow, not to mention
Playing sounds and performing attacks should only be called and automatically be called when the player is performing an action called "Attacking" or otherwise named. My point being that when you have a state called "Attack Phase" you can slide permission for the static attack function call to be set to true, for THIS object even would be an even better specification, as globally accessible functions do not differentiate between anything unless caught. Hence my conclusion to use Player as an object and modify it when a master controller decides it gets to do anything at all, all actions the player can perform should be methods inside the player, all public, all encapsulated except the user input requests marked as public , the rest is not accesible and just does the real work. (Public private , if you just went WTF , you can mimic it here if you want )
If you want to skip keeping track of states, and ignore the permissions set to who can call what when in a turn based game, I will simply tell you , test , test , test again, pray it works.