How can I build a base in Terraria that is safe from Old One's Army events?

To build a base in Terraria that is safe from the Old One's Army events, you need to understand the mechanics of the event and how it interacts with your world. The Old One's Army is a wave-based defense event triggered by placing an Eternia Crystal Stand and an Eternia Crystal. The event spawns enemies that attack in waves, and the goal is to protect the crystal from being destroyed. If you want to ensure your base is safe from this event, you need to carefully plan its location and design.

First, the Old One's Army event only occurs in specific locations. The Eternia Crystal Stand must be placed on a flat surface that is at least 61 blocks wide and 10 blocks tall, with no obstructions like walls or platforms. This area is called the "arena" for the event. If you build your base far enough away from this arena, the event will not interfere with your base. A good rule of thumb is to keep your base at least 100 blocks away from the arena to avoid any accidental overlap.

When designing your base, consider building it in a location that is naturally protected, such as high in the sky or deep underground. Sky bases are particularly effective because most enemies, including those from the Old One's Army, cannot reach you unless they have flying capabilities. To build a sky base, you will need a lot of building materials like wood, stone, or any other block type. Start by creating a platform high above the ground, at least 200 blocks up, to ensure safety from ground-based enemies. Use ropes, wings, or a grappling hook to reach this height during construction.

For underground bases, dig deep into the earth and create a secure area with strong walls and lighting. Use materials like stone bricks or dungeon bricks to reinforce your base and prevent enemies from breaking in. Make sure to include multiple layers of defense, such as traps and lava moats, to deter any intruders. Both sky and underground bases should have proper NPC housing, storage, and crafting stations to make them functional.

Resource management is crucial when building a safe base. Gather materials like wood, stone, and ores early in the game to ensure you have enough to construct your base. Use a pickaxe and axe to mine resources efficiently, and consider setting up a tree farm near your base for a steady supply of wood. For advanced materials like stone bricks or glass, you will need a furnace and a kiln. Plan your resource gathering trips carefully to avoid running out of materials mid-construction.

Class and equipment considerations are also important. If you are building a sky base, having wings or a flying mount will make construction much easier. The Spectre Wings or the UFO Mount are excellent choices for mobility. For underground bases, a good pickaxe like the Molten Pickaxe or the Drax will help you dig quickly and efficiently. Equip armor that boosts your defense, such as the Molten Armor or the Turtle Armor, to protect yourself from any enemies you encounter while building.

Common mistakes to avoid include building too close to the Old One's Army arena, not reinforcing your base walls, and neglecting to include proper lighting. If your base is too close to the arena, the event could spill over and damage your structures. Weak walls can be broken by enemies, so always use strong materials. Poor lighting can attract enemies and make it difficult to navigate your base, so place torches or other light sources regularly.

Advanced techniques include using actuators to create hidden doors or traps, and wiring mechanisms to automate defenses. For example, you can wire dart traps or flame traps to activate when enemies approach, providing an extra layer of protection. You can also use teleporters to quickly move between different parts of your base, making it easier to defend during emergencies.

In summary, building a base safe from the Old One's Army requires careful planning, resource management, and strategic placement. Keep your base far from the event arena, use strong materials, and incorporate advanced techniques like traps and wiring for added security. With these strategies, you can create a base that is both functional and safe from the chaos of the Old One's Army.