Annihilargh

The Anihilaarg was an extremely powerful and dangerous weapon used by the ancient Contemelia. It looks like a purple box with a red light inside it. The Anihilaarg had the power to destroy an entire universe when activated.

Backstory
The Anihilaarg was used by the Contemelia as they traveled across the multiverse playing practical jokes on the inhabitants, if the Contemelia did not like a particular universe, they would use the Anihilaarg to reduce it to nothingness. At some point in time the Contemelia died off, but their vessel still flew across the multiverse labyrinth, as it passed into legends along with its weapon. It first appeared in So Long, And Thanks For All The Smoothies, where the vessel appeared above the Earth and Argit was sent aboard the ship by Incursion Emperor Milleous to obtain the Anihilaarg.

Later in the episode, it was accidentally activated when Ben, Rook, the Incursions and the Vreedle Brothers were fighting to obtain it. It destroyed the entire universe, but Ben recreated it using Alien X. With the Anihilaarg already activated, it's purpose of destroying a universe was complete and was rendered useless as a weapon now. Everyone present believed that the Anihilaarg was defective, unknowing that the universe was even destroyed in the first place as Rhomboid Vreedle went over and crushed the Anihilaarg underfoot, destroying it completely.

Trivia

 * All throughout the episode, Ben had a hard time of pronouncing its name, causing everyone else to say it for him. However, he finally said it right when he was the voice of reason for Alien X.
 * It is said that the Anihilaarg isn't even it's full name, saying that "Anihilaarg" is all that could be said of its full name before it is activated.
 * This is a clear reference to "The Castle of Aaargh" from Monty Python and the Holy Grail, as it was believed that it was all that was written by the original writer before he died.
 * In the Spongebob episode, "Graveyard Shift," Squidward tells Spongebob about a ghost called the Hash Slaying Slasher, but that most people can only say "Hash Uuaaggh," before he gets them.