Paper Mario: Super Seal

If you paperize the area around a circle of flippable flowers, you will see a stickable area appear. Stick a sticker and a "?" block will appear. Inside the block will be a more powerful version of the sticker you originally stuck.

After beating the game (and watching the credits), the screen will shift to the book from the start of the game. The book closes and the light turns off. At this point, just wait about three minutes. A hidden lullaby song will start to play, and will continue to play until you hit a button.

In the background of certain levels, you can spot Mario's brother Luigi, who can be peeled off the level by Paperizing. If you peel him off in all 5 locations, he'll appear during the credits sequence. In addition, each individual peeling will unlock a rather amusing newspaper article in the leftmost house in Decalburg's Residential Area.

Megaflash Stickers are the rarest and most powerful battle stickers in the game, but each one will only ever appear in one set location, (except the Megaflash Hurlhammer, which appears in two) and some can be very tricky to find. However, once you know where to find one, you can get as many as you want, so it helps to know where they all are.

You can unlock the following exhibition rooms by completing the 2 sections of the museum collection:

There are eight Achievements you can achieve in this game. They can be achieved at any time, and through a number of conditions. However, it is worth noting that, after completing World 1-6 and getting the first Royal Sticker, there are eight Super Flags in the Sticker Fest area of Decalburg. You can examine them to check on your progress to the Achievements.

While going through World 3, Wiggler's segments will be separated, and you will have to find all 4 to access the boss. However, after you "subdue" a segment, it will follow you anywhere you go in World 3, and if you take it to specific places, it will inspire the segment to write a new page for Wiggler's Diary. Note that it doesn't really matter which segment you take where. Also, be warned that these are the ONLY permanently missable things in the game, so be sure you have all five before returning the fourth segment to Wiggler.