The Basic Health Potion is a healing-potion made from a starting-recipe that you already have when entering a new Creativerse-world. You can craft it in your Crafting Menu (default key "Q") or at any Crafting Table in worlds created before R22 on September 16th 2015. Crafting or taking a Basic Health Potion (from a friend's chest/bag for example) for the first time will automatically unlock the recipe for the Advanced Health Potion. Basic Health Potions will instantly heal circa one third of your character's Health (red bar), no matter if in full armor or without any.