What is this item?

[GinGin]

I saw it last year. This item looks like.. orange shape slime that hanged in cross. And when it get damaged, it shows damage and move luke bobblehead. What is this item?

 

[Droffy]

It sounds like the Mmmmmmmmmmm mod the dummy that you can hit to see how much damage you are doing

 

[erindalc]

Or alternately it also existed in balkon's weapon mod I believe, although I can't recall if it showed damage. The post above is more likely correct.