Note: This show goes by the name Sgt. Frog in the official dub version. However, its Japanese name is used far more often.
A girl with a transforming head piece uses it to make herself into a faux-gorgon and turn two girls to stone before accidentally turning herself to stone in a mirror. Once a victim looks into her eyes, they have a second of normalcy to realize they've looked before being enveloped in purple light and a gray cloud. Once the cloud goes away, a stone statue is all that remains.
The first two victims are a ninja and a girl in a robotic-flying suit. The girl in the flying suit turns to stone in mid-air and falls to the ground unscathed after her petrification. Both of those victims return to normal shortly after the faux-gorgon turns herself to stone. She herself returns to normal and presumably leaves off-screen while the other characters are talking.
From Wikipedia - Fuyuki has a dream about a girl who hunts unknown beings like aliens. She turns out to be real, and she has her eye on the Keroro platoon. Her name is Alisa, and she kidnaps Fuyuki, because he has the power to attract the creatures. The Keroro platoon come and chases her, but she locks them up in a box. The humans rebel, but she also has the power to turn people into stone. All looks bleak as almost everyone is defeated.
It's worth mentioning that Alisa is in fact a living doll herself with the shape shifting headpiece actually being her father. However, she appears mostly human, so no doll-related ASFR material comes of it.
|"A good scene with a few cute victims. The art style is more adorable than beautiful which is fine, but the actual statue effect isn't all that decent. The poses are great though."||3/5||StoneLad|