Minecraft wiki entry for Surviving_in_a_single_area_indefinitely, associated text: For making potions, you will need glass bottles. This may seem to be a problem however, as glass bottles require glass or sand. Neither are feasibly renewable pre-village and may not spawn at all in a SkyBlock world. What you will have to do is get witches to spawn and drop a glass bottle, or fish up a water bottle. Keep in mind that witches are rarer than other mobs. The only way to acquire gold in SkyBlock is to kill zombified piglins, find a river biome and farm drowned, or smelt gold equipment. Wandering traders, however, can spawn anywhere and sell most items or blocks needed for skyblock. But, their trades can be useless as a player needs emeralds for them and most of the prices are somewhat expensive just for a single item.