Bug Shell is an object unobtainable by players through normal means. This item's information is present in the game files, but not intended by developers to be in players' possession.
This Item Is Only Command Spawnable
You Will Not Find This Anywhere
This Item Was Reimplemented Back into the game in Version 1.4.4
On the Release date July 19th, 2019
Bug Shell is a crafting material. It is currently implemented.