It can be crafted in your Crafting Menu (default key "Q") or at Crafting Tables (that still exist in worlds created before R22 on September 16th 2015), but only after the crafting-recipe has been unlocked upon taking a Glob of Goo for the first time (as occasional loot or pet-harvest from most Creatures, including Pigsies). To craft 8 Blocks of Goo at a time, you'll need (as of R29 in February 2016): * 2 Globs of Goo (from most creatures) * 1 Stone Rod made of Stone, Limestone or Bedrock in a Processor