Setting up Anime-Game-Launcher

This one is definitley more complicated and requires you to have flakes setup.

In your flake.nix:

  inputs = {
    aagl = {
     url = "github:ezKEa/aagl-gtk-on-nix";
     inputs.nixpkgs.follows = "nixpkgs";
    };
  };

  outputs = {
    aagl,
  }

Then under nixosConfigurations

    nixosConfigurations = {
      yourSystemName = lib.nixosSystem {
        # ... Your code
        modules = [
          # Your imports and modules
          {
            nix.settings = aagl.nixConfig;
            imports = [ aagl.nixosModules.default ];
            programs.anime-game-launcher.enable = true; # Impact Game
            programs.honkers-railway-launcher.enable = true; # Railway game
            programs.honkers-launcher.enable = true; # 3rd game
          }
        ];
      };
    };

INFO

For reasons I can't type the actual game names here but basically pick any of the game you want from the ones the code snippet and just remove the programs you don't want.