It might've been around two months since The Super Mario Galaxy Movie was released, but fans are still spotting new Easter eggs – and the latest one is seriously impressive.

In one of the Super Mario Galaxy Movie post-credits scene, we get a look at the prison holding Bowser and Bowser Jr. Look a little closer, though, and you'll notice it's a perfect retro reference.

Yep, the prison is actually made from a stack of NES cartridges, which is the most fitting throwback imaginable.

There are tons of Super Mario Galaxy Movie Easter eggs, so it's not a huge surprise that this one flew under the radar. Still, I'm very glad it's finally been spotted.

While the film stormed the box office, drawing in almost a billion dollars to date, its critical reception was more lukewarm, with a score of just 42% on Rotten Tomatoes.

"Actually, I thought the critics' reviews of the first film were understandable," Mario creator and executive producer Shigeru Miyamoto has reflected. "But I thought this time it would be different... and it was even harsher than last time, which I found strange."

Our own Super Mario Galaxy Movie review awarded the film 3 stars and reads: "The Super Mario Galaxy Movie surpasses the original thanks to relentless energy and creativity, but its starry-eyed ambitions fizzle out thanks to the bizarre treatment of Brie Larson's Rosalina and an undercooked story."

For more, check out our guide to all the most exciting upcoming video game movies to fill out your watchlist.