How to make an animation that is triggered wherever the character is?

What exactly do you need to stop, as if the game was paused.

I want the game to pause so things don’t happen around the player (like enemies attacking) while the animation is playing and the player has no control. But since I want the character to play a celebration animation, I can’t just pause the game completely. So basically I want everything to pause except for the player character.

Getting a list of all actors sounds very ‘expensive’, wouldn’t that heavily affect performance?