Photon
Terrarian
Someone discovered a duck exploit (I don't know who, but I heard about it, if you know who did then say it) in which you can use duck statues and water to spawn a large quantity of ducks, preventing other NPCs from spawning. This works in 1.3.5.3. I tried building a similar machine in my game and then trying it to see if it can prevent the almighty Dungeon Guardian from spawning. Apparently, the machine does effectively prevent it from spawning in pre-Skeletron worlds. No dungeon mobs will spawn nor will the Bound Mechanic, but it is possible to obtain a key from pots for a wooden chest and obtain dungeon loot. (But, the contraption needs wiring, which defeats any useful purpose of this. It's mostly a novelty) Multiple machines are required if you want to go very deep. I usually place one around 50' Surface (depth meter) and 180' Underground. The first needs to be on so you can build the second. This glitch might be patched out in 1.3.6, when it does come out.
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