|The title of this article is unofficial; an official name hasn't been found, so it's been given a fitting title by the editors of this wiki for amenity, either from a popular fan-name or a mere description of the topic. If an official name appears, then it should be moved to the official name.|
Twisters (ツイスター Tsuisutā) are green, blobby-like creatures with white spheres circling them that appeared as stage enemies in the PC-98 game Story of Eastern Wonderland, specifically on stages 4 and the Extra Stage. It's unknown what their real names are, what they're associated with or if it was Rika who created them. As they enter the screen, they'll continuously move slowly towards Reimu Hakurei and Genjii, but then pause after approx. 2 seconds. As they pause, they'll shoot some bullets towards Reimu for her to dodge, then spend another 2 approx. seconds homing towards Reimu. If defeated on Lunatic, they'll throw bullets directly at Reimu as return fire. On the Extra, their bullets shoot outwards in a circle and are non-trivial to deal with since a big group of them comes on the screen.
The name "Twister" is uncommonly used in the Japanese fan-base, either likely to reflect their appearance as the way they twist around in their sprite animation, or it's based on the Twister from the Kirby series since they both vaguely resemble each other, especially with the spherical hands.