Kai (Secrets of the Forbidden Spinjitzu)

The Kai (Secrets of the Forbidden Spinjitzu) minifigure is highly desirable for Ninjago collectors due to its unique design elements tied to a specific story arc. The reddish-brown belt and leg wraps detailing, combined with the unique head print featuring a bandage and scar, capture a pivotal moment in Kai's journey, making it a standout version of the character.

The Pearl Titanium shoulder guard is also a notable element that adds to the minifigure's visual appeal. Given Kai's central role in the Ninjago storyline, any variant of him tends to be popular, but this particular version's distinct look and the fact that it appears in only a few sets enhance its collectibility.

This version of Kai appears in only three sets, all released in 2019 and now retired, increasing its relative scarcity on the aftermarket. While not a limited edition or convention exclusive, its limited set appearances contribute to its desirability among collectors trying to complete their Ninjago minifigure collection.

As a key character in the Ninjago theme, Kai minifigures generally hold their value well. This 'Secrets of the Forbidden Spinjitzu' version, with its unique design and limited availability in retired sets, has good investment potential. The Land Bounty set (70677-1), being the largest and most expensive set containing this minifigure, could further drive up demand for the minifigure itself as the set becomes harder to find.