Stickers are important elements in Paper Mario: Sticker Star. They serve as Mario's main method of attacking, and as such there are a wide variety of stickers to attack with. They are also used to solve puzzles and unlock pathways. Stickers were originally round-shaped, then changed to hexagonal before they became square-shaped in the final game. Additionally, Mystery Box stickers were planned as seen in artwork, but they do not appear in the final game.
Stickers come from the Sticker Comet. Once every year, they rain down on the Mushroom Kingdom during the Sticker Festival. After Bowser accidentally shatters the Comet and scatters the Royal Stickers, Mario is forced to retrieve them with the help of Kersti, a sticker being who is the caretaker of the Sticker Comet. Along the way, stickers are used to solve puzzles and battle enemies.
Stickers can be found almost everywhere. Battle/item stickers are sorted into seven different categories by strength; Worn-Out, Normal, Shiny, Flashy, Big, Big Shiny, and Megaflash. They are sometimes dropped by enemies, found on walls, found in ? Blocks, bought at shops, etc. Collected stickers are kept in Mario's album, and each page in the album is 6-by-10 spaces (which can hold 15 small stickers in a 3x5 arrangement). Stickers can only be kept as long as there is space in the album, and certain stickers take up more room than others. In order to maximize usage of space, it may be necessary to rearrange stickers or even remove them. Pressing while looking at the sticker album will automatically re-arrange all stickers to maximize free space. This setup usually consists of two large stickers in a corner surrounded by smaller ones, though it varies depending on the size of the stickers collected.
The Sticker Album is grouped into different tabs:
Stickers vary in size. The three different sizes stickers come in are:
There are 96 battle stickers in the game.
These stickers are plot-related, and are only available in certain battles. These two stickers are not required for the Sticker Museum.
Things are objects that can be found within the game. They are named such because, unlike most of the denizens in the game, the items are not actually made out of either paper or similar material such as cardboard. There are a total of 64 things throughout the game, each with a different purpose. Mario finds them as actual objects, and they cannot be used in this state. Although they are not made out of paper, as noted before, they can be rendered into stickers by flinging them onto a special board at a Sling-a-Thing location. In addition, a specific Toad in Decalburg will sell things in a manner that is implied to be illegal. The player can then take the sticker and either paste it on the environment to cause events or use them in battle. Although not directly stated within the game, the player can execute Action Commands up to "Excellent" on most things by pressing or, in the case of the Cake, blowing into the microphone. Mario can only carry one of each Thing at a time, whether in normal form or as a sticker.
Scraps are pieces of the environment that can be removed and pasted into a certain location later on. They can either be obtained on their own or by peeling a certain piece of the environment off by paperizing, and can be placed back in their proper location with the same process. Removing something from the environment results in a void appearing in its place, which shows where the removed scrap or even another scrap is to go.
Throughout the game are hidden spots that can convert stickers into stronger stickers. They are usually found above a hexagonal formation of flowers or tree stumps, and only support the smallest stickers. Below are the possible outcomes of an upgrade: