Cubicula-by-Vaclav-Obsivac-(aka-Vinco)
Craftsman: Vaclav Obsivac
Designer: Vaclav Obsivac
Found at: Eureka
The fitting is somewhat loose on this one (only have two prior to this one though), but it’s really fun and difficult!
But if I had to choose only one (of the ones I have so far) my choice would be Explosion cube