Theoretically, you could fly out of the universe on one side of the bell and arrive back on the other.

Like the Atari Game "Asteroids" move off one side of the screen and appear on the opposite side. Perhaps this horn is more like a loop? Lopsided on one side, but connected.

Ouroboros shaped perhaps? [link|http://abacus.best.vwh.net/oro/ouroboros2.html|http://abacus.best.v...o/ouroboros2.html] [link|http://en.wikipedia.org/wiki/Ouroboros|http://en.wikipedia.org/wiki/Ouroboros]

The larger part, the horn part that is larger, could be the head, the rest could be the body or tail.