Lunar Deconstructor is crafted with 10 lunar fragments of each type and 10 lunar bars at the Ancient Manipulator. On right clicking, the deconstruction UI opens. You can put in an unsealed lunar cube and an item to search for recipes. Then, you can choose which recipe you want to seal in the cube, for a price. Cubes can be unsealed with a right click, traded with players, works in multiplayer. Some items have failure rate in place, such as potions, flasks and lunar fragments. This is to avoid exploiting.
You can craft a Lunar Cube at the Lunar Deconstructor with 1 of any Lunar Fragment and 1 Lunar Bar. A 'Queer' Lunar Cube is crafted with 1 Lunar Cube and 1 of any Lunar Fragment at the Lunar Deconstructor. A Queer Lunar Cube can be sealed and unsealed without being destroyed, a Lunar Cube can be unsealed once before being destroyed. Queer Lunar Cubes are recognizable by their morphing colors.
The Lunar Deconstructor will show which cube is currently being handled (when one is put into the UI that is) Mod comes with fitting sound effects.