Do you mean by 'full head sinks' a closeup of sinking under, or just sinking under?
In real life, feeling the mud sliding over my face as I go under is one of the best feelings. Unfortunately, I've not got any video of this sink, only some still images but I could use AI to recreate the sinking under experience by taking a photo from when I was chest deep in the mud. This was using the Hailuo 2.0 standard model on flux.ai, which appeared there recently. It seems the easiest model to make a sink under in sloppy wet mud without the mud just turning to water. (Other models seem to do well with dry sandy mud but my preference is for wet slimy stuff). All in all the model did a pretty good job of depicting the mud as it actually was in real life.
mw_disappears.mp4
It also makes the mud flow quite well, note how it flows around the bill of the baseball cap, which I've not really seen with any other models so far.
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