You can choose!
Read the article or watch the movie. Both contain (almost) the same content.

I didn’t embed the video directly to avoid any tracking from Google and complications with the DSGVO.

I stumbled across this funny video and after a short period of lolling I was thinking… maybe this isn’t a bug at all!

What we see here is either the result of a little torture fun of an opposing Mafia family or it’s a neat little trick to avoid clipping between hat and hair (only that the guy in the video has no hat – which is the actual bug).

Here is how it looks when you just put a hat on a Mafia II guy:

What can we do about the clipping? We already saw the solution in the first video. They just compress the upper head a bit:

But how did they do it? At first I thought it’s a vertex shader pushing the vertices a bit but I couldn’t find proof by studying the draw calls.
So I got some mod tools (M2Toolkit and M2CharMC), extracted the meshes and found something! There is a bone called “HairScale” in the rig and this is how it looks when scaling it up and down:

VoilĂ ! With that, we can put the hat on, scale the hair bone down and schwups, our little Mafia men is happy!

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