On a knitted island filled with many Yarn Yoshis of varying patterns, the evil Magikoopa Kamek turns nearly all the Yoshis into bundles of yarn for his master Baby Bowser, scattering them across different worlds. However, two Yoshis manage to avoid being transformed themselves, and they set off to pursue Kamek and rescue their woolly friends. After traveling through six different worlds, Yoshi manages to storm Baby Bowser’s castle. When Yoshis reach Baby Bowser, Kamek reveals that he stole the yarn so that he could use it to grow Baby Bowser to a much larger size. After battling Baby Bowser, the Yoshis rescue their friends from Kamek and Baby Bowser. Kamek and Baby Bowser fly away, but crash land on the moon.