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The Aurora Block is a powerful, rainbow-colored block used in Mario & Luigi: Partners in Time. It has the ability to grow to match the size of the heart of the person who strikes it, and it is celebrated in the Star Realm.
During the events of Mario & Luigi: Partners in Time, Mario, Luigi, Baby Mario, and Baby Luigi find a talking gate at the Star Shrine who tells them that they cannot continue unless he "reads" them to see if they're worthy or not. Although Mario, Baby Mario and Baby Luigi have enough courage to pass the gate's test easily, Luigi is not as fortunate. The star gate gives them three options: go home and eat some pasta, continue without Luigi, or find the Aurora Block.
The team chooses the third option and sets off to find the Block. They discover it quite easily, but Luigi is unable to hit it, with the block moving out of the way whenever he tries. The gate then asks Luigi a trick question that he can't answer and is rude to Luigi afterwards, causing him to cry. Mario then stands up for Luigi.
After that, the Star Gate finally comes clean and reveals that this was all just a test to measure their brotherly togetherness. He then gives them the titles of "best siblings ever" and tells them that they're all ready to proceed to the rest of the Star Shrine. Best of all, the gate lets the confused Luigi hit the Aurora Block, which he does. However, it is then that the gate chooses to tell Luigi that the Aurora Block can grow to the size of the heart of the person who hit it, and, after he says this, the block turns gigantic and comically flattens Luigi. Baby Mario picks the pancake plumber up, and the Star Gate opens.
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