This is going to be a weird and very short article, but I thought that the topic deserved a list. When I say powerups, I mean the five items that are hidden in ? blocks and do not enter into the inventory, such as the Mega Star. Most of these are rare and not all that useful, but they are fun additions to the game. Almost every "powerup" isn't actually helpful to combat, but instead give coins or points.
#5 - Happy Flower
The Happy Flower is fun! And happy... When Mario finds one of these, coins start raining down from the sky. The problem is that it's hard to get a lot of coins from this item, and more often than not you'll end up falling in a pit and only ending up with like ten extra coins. Simply put, if you find one of these, grab it for the fun, but the benefit will be minimal.
#4 - Pal Pill
The Pal Pills are my least favorite powerup in Super Paper Mario, but they're more useful than the Happy Flower. Each of the eight "pals" can take out one enemy and then it dies. Oftentimes, the mini, 8-bit, characters just fall in pits or kill enemies that could have been easily taken out by a Pixl more efficiently. While the Pal Pill isn't harmful to the player, it's benefits aren't really needed.
#3 - Speed Flower
The Speed Flower makes the active character move faster than usual, and triples the points earned from any action (except for items that give points, which are multiplied by six). Movement under the effects of the Speed Flower can be tricky, but with enough precision, the point boost can be helpful towards that next juicy level up. Also, using Dashell while under the effects of a Speed Flower is fun.
#2 - Slow Flower
The Slow Flower is almost exactly the same as the Speed Flower, but, well, instead of speeding up time it slows down time. The reason the Slow Flower places higher is that it is much easier to precisely jump on enemies and hit blocks when slowed down rather than sped up. But other than that, the powerups are basically the exact same.
#1 - Mega Star
Although the Slow Flower is my favorite powerup, no other powerup comes close to the one-shotting powers of the Mega Star. This powerup transforms the active character to a giant, Pixl'ated version of themselves. Any enemy in their path will be decimated. The Mega Star is basically just a way to give the player some more points, because every section these are found are full of enemies.
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