My friend and I used this on grief in the town, and oh my god we were laughing our asses off. Its so funny to do it and then see your opponents (and noobish teammates) try to get in to use the mystery box and get really frustrated when they can't get through the barrier. It ruins the gameplay completely, but it is so fun. If you're able to get juggernog before anyone opens the bar/diner (in the town) and then open it with the glitch, you can probably survive there forever, just by running trains and using the mystery box. And whenever the mystery box gets a teddy and spawns outside the diner, you just wait for your teammates and opponents to use the mystery box and send it back to you. It's perfect.
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