These TK16 kendama have been showing up in various places since around the time of the World Cup 2015. They have been rumored to be the design of the old Mugen (light blue seal). They are also promoted elsewhere as the “new” shape of the TK16. Neither of the rumors are correct.
We have spoken directly with the president of the manufacturer and have been told that they are an aberration, a mistake. There are no plans to continue making this version and all future versions should return to the original shape.
If you want to own a piece of history or just like the different shape then grab one of these MUTANT TK16 kendama today. We have a very limited number of the blue MUTANT kendama and do not expect any more in future shipments.
Note that the primary differences are the shape of the ken as it reaches the slip grip ridge, the size and bevel of the tama hole, and color.