Detective Pikachu still has fans discovering new things about it a year after its release — no doubt because most consider it to be the film that broke the "videogame movie" curse. In this latest instance, someone has discovered an easter egg within the movie that references a core mechanic found in the Pokemon games.

A film fan going by the handle "Movie Details" on Twitter was the one to point this reference out to others. As most can probably guess from the name, the account exists to point out easily missed details from movies. In this case, the film happened to be Detective Pikachu.

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The Easter egg appears in the scene where Detective Pikachu finds himself in an underground cage match with a feral Charizard. When things inevitably go sideways, Tim, Detective Pikachu's "trainer," tells him to run. Pikachu attempts to do so, but every time he does, he fails, and therein lies the Easter egg.

Players are not allowed to run from Pokemon trainer battles in any of the Pokemon games. If they attempt to do so, the game will present them with a prompt saying, "No! There is no running from a trainer battle," and then force them to continue the match. This same rule is physically applied to Pikachu through the cage when he tries to run from the battle with Charizard.

The rule comes from another that the games enforce, which says that once trainers lock eyes, they must do battle. It's why every time the player character is caught by a trainer while minding their own business, a battle ensues. If players could forfeit the fight, there would be no point in this rule existing. Besides, Pokemon games are already too easy to beat without the ability to give up on matches.

Precisely why the first rule exists remains a mystery, but it's probably to keep the game world feeling alive. NPCs don't move unless they spot another trainer to battle. If they didn't stroll up to the player to start something, the avatar character would be the only thing that ever moved — them and any following Pokemon.

Swimmer and Runner trainers move on their own, but not enough to warrant the rule's exclusion. And while Pokemon cutscenes move things too, they rarely ever result in trainer battles, which are the game's core mechanic. Of course, Pokemon Let's Go Pikachu and Eevee are excluded from this.

Detective Pikachu is available now on digital, DVD, and Blu-Ray.

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