This article is about something not canon to either the storyline of the TV show, Ninjago, or the LEGO Movie franchise.
The Golden Star Hammer is a LEGO Ninjago: Masters of Spinjitzu weapon used mainly by KendoZane. It appears to be a black-and-gold hammer with a small, spiky head made of two hammerhead segments (actually a pair of golden Shurikens stacked on the tip of the shaft). It is apparently designed to strike with the maximum amount of force, and works best at close range.
Stay cool with Zane's favorite hammer of calamity. Not just a pretty design, this versatile star will always hit its target with maximum force. Strike up close for best results.