Plants vs Zombies, PopCap's tower-defense game first released in 2009, made its shambling garden invaders instantly recognisable, and the box-carrying zombie became one of its most memorable sights. As clips from the game circulated on soundboards and in gaming videos, this short groan and shuffle was lifted out of gameplay and reused as a quick shorthand for a slow, stubborn intruder. It remains popular because it is instantly recognisable to players, funny without needing context, and short enough to drop into memes, edits and reaction videos.