What's that weird round pink creature with a cute face and very short arms and big foot?
Is Kirby! from Nintendo. He can turn to a pink ball and whack enemies.
Kirby is very popular in Japan and US.
Here're detailed facts about Kirby taken from Wikepedia
Kirby (カービィ, Kābī?) is the main character of Nintendo's Kirby video game series created by Masahiro Sakurai and developed by HAL Laboratory. The Kirby series is one of Nintendo's many well-known game franchises, spanning nearly twenty games since 1992. His first appearance took place in the 1992 video game Kirby's Dream Land, where he was portrayed by a two-dimensional sprite; he has also been conveyed by a three-dimensional computer-generated image in some games. He has been featured in other video games from Nintendo, on Nintendo's merchandising, on comic books, and even on a television show about the Kirby series.
Kirby is described in his games as a small, spherical creature who is a denizen of Dream Land (プププランド Pupupu Land) on the planet Pop Star. In the main games, he almost always has the same abilities; he can walk, run, jump, float, and inhale, spit out or devour his enemies. Most of Kirby's games adhere to the same basic idea; that his is a series for beginners, not only children. As such, his games can be beaten by a player of nearly any age, but offer deeper challenges for more experienced gamers.
Kirby often journeys across the planet Pop Star, defeating evil forces such as the greedy King Dedede or the ominous Dark Matter. On other occasions, he encounters the enigmatic Meta Knight. To defeat his foes, he uses his signature ability of inhaling large objects and spitting them out with great force. From Kirby's Adventure and onwards, Kirby was able to gain the abilities of the enemies he swallowed, aptly known as Copy Abilities. In several games in the series, he obtains a mystical weapon during the climax of the battle against his enemy; this weapon is usually required to defeat the final boss.