The Abandoned Lab can only be initially visited in Hardmode, after the player has defeated all three Mechanical Bosses attempting to visit the Lab prior will unleash invincible Laboratory Drones that will relentlessly attack the player. It's recommended to acquire the IO-Locator accessory and equip it before trying to find the lab. The Abandoned Lab will always be generated at the same location, depending on map size: With its dangerous defenses and debuffs, the player must exercise caution prior to entering, it size is similar to temple. Unlike other areas in Terraria, the Abandoned Lab has a static structure and will always be the same in all worlds. The Abandoned Lab is a massive underground dungeon that generates upon world generation. The white path is accessible post- Mechanical Bosses, and red path is accessible post- Moon Lord. Map view of the Abandoned Lab, along with the direct path to the end (click to enlarge).
