Terraria Floating Brick Fortress with Traps
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Here is a fortress house built in Terraria. It is able to house 18 NPCs and is well-protected from most hazardous events.

Features

Features
- Floats above ground to prevent access by most mobs.
- Spiky ball, flame, and spear traps connected to a switch.
- Built from incorruptible gray brick.
- Able to house 18 NPCs with quick access to all through central shaft.
- Outer layer "buffer zone" to better protect NPCs.
- Six protected access points.
- Mine shaft rope access to underworld hell.
- Heart lantern and campfire buff in range.