So .... Grok. It's very good at making this kind of slime clip I like the best. A few examples attached as gifs. I'll put some more together into a video clip soon. The generated audio is still poor, but I don't mind that much. And overall it's pretty wild.

But, mixed feelings. Personally, this is starting to get dangerously close to instant gratification that could feel potentially addictive. (Lucky me, I can get so excited for 5-second clips.) Plus they're keeping their guardrails down despite plenty of people out there misusing it ...

Anyway, prompts follow in separate replies below, if anyone else wants to try drinking from this poisoned chalice

It works better in two steps -- make the image first, then the video from the image. The prompts can of course be tweaked in all kinds of ways, it's pretty responsive to the instructions.

Image prompt example:
A video clip from a 1990s sitcom featuring two women around 25 years old, sitting close together and talking, in tight closeup. They are attractiveland distinctive looking, and they are sexily dressed for a first date. they have contrasting ethnicities, styles, emotions, hairstyles, and personalities, with bold makeup. They are shown from the waist up.
Background: a seamless plain light blue background.
The video is captured under soft, even ambient lighting, with natural tones, high clarity, and a bright, lively atmosphere full of youthful, everyday energy.

Video prompt example:
1980s video. the camera stays still. The video is captured under soft, even ambient lighting, with natural tones, high clarity, and a bright, lively atmosphere full of youthful, everyday energy.
Woman 1: on the left
She is complaining to her friend and says "I don't know what you could possibly ..." which causes her to be interrupted by clumpy wet opaque olive-green cake batter, which trickles down roughly from high above her in a narrow irregular stream, captured with motion blur. The batter follows a slight arc as it falls, like the substance is being dumped out of a bucket which is offscreen. The video emphasizes the texture of the batter, which is watery and liquid but with a lumpy consistency like wet oatmeal. The feeling is playful and sexy, but also gross. It keeps impacting her head. Only AFTER the batter impacts her, she is caught completely off-guard, giggly and amused but grossed out. But we only see that expression for a split second before the pouring batter covers up her face completely. As it hits her, the mess starts to completely cover her face, hair, shoulders, outfit, and arms. After a couple of moments we can't see her face anymore because it's completely covered by the splattering batter. The stream of mess keeps coming and coming. More and more of the batter keeps landing on her body, and she gets gradually more and more covered in it. She then tilts her head back slightly, giving into the batter, helplessly holding up her hands. It just keeps falling from above and flowing over her, thicker and thicker and coating her completely top to bottom, spattering off the top of her head all the while.
Woman 2:
Meanwhile, the other woman cringes and stays still, shaking her head sympathetically with her eyebrows raised, helpless against the significant amount of mess which spatters onto her too. She tenses and cringes.

Outstanding, thanks for sharing!!