Boxes (Crates) are found underground, and have different breakabilities.
Currently, there are four different ones, which require better and better tools to break.
They usually contain tools, Wooden Planks, and metals.
Level 1- Found near surface, mostly Wooden Planks and Nails .
Level 2- Found sligtly deeper than Lv. 1, and contains similair items.
Level 3- Found at moderately deep levels, and contains wood tools usually.
Level 4- Found at around 3/4 of the way to Bedrock. Contains up to iron tools.