Probably this apparently hand made custom of one of the more recognizable creatures from the infamous unlicenced 70's Kaiju trading card series, Pachimon.
True to the source material in question, it's body is that of Antlar and it's arms are that of Baltan. Both seem to be parts from official Ultraman vinyls that have been airbrushed.
The oversized skull however is a hollow hard plastic that almost seems like a random Halloween decoration repurposed. It's way too big, likely chosen because it matched the diameter of Antlar's neck socket, not because it was the right size.
No idea who made this, but it's a fun oddity.