Don’t store it in the Level BP because you can’t access the Level BP from anywhere else. For example, you can’t Cast to it and pull variables, values, functions, etc from it like you can other blueprints. I do all my BP references in my custom Player Controller because the player controller is easy to get from any other BP by Casting to it. Other good spots might be Game Mode or Game State though you should be careful of putting too much in those BP’s. Player Controller (a custom one) is probably the best place because it’s automatically instantiated when the game starts and stays persistent throughout the level (but changing levels during gameplay will reset and reload your controller.)
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