The Super-Secret Canadian Mind-Control Device

In the center of Little Canadia, you find a strange device, covered with knobs and dials and blinking lights. A label on the side of the device reads "Super-Secret Canadian Mind-Control Device."
It's just as you've always suspected! The Canadians are secretly in control of all of the monsters in the Kingdom.
The device is currently set to level X. Note that the dial goes to 11. Most mind-control devices have dials that go up to 10, but this one goes to 11. It's one higher.
Notes
Located in Little Canadia, an area only accessible to players who have ascended with a Mysticality zodiac sign, this device has a dial which supposedly controls all the monsters in the Kingdom. The dial goes from 0 to 11.
On the forums it has been suggested (and backed up fairly well) that if the dial is between 0 and 10 it simply adds that number to the level of every monster you fight, anywhere in the kingdom. Though previous theories said that at 11, the dial makes the monsters significantly more powerful than it would at 10, this has since been disproved, and it's been shown that setting the dial to 11 only adds 11 to the level of monsters.
If you have the dial set at 11 and defeat Baron Von Ratsworth, Boss Bat, Goblin King, and the Bonerdagon you gain the Boss Boss Trophy. The Baron was not previously required for this trophy, but is now.
Attempting through possibly unscrupulous means, to set the dial to a number that is out of the valid range yields the following message: "Invalid dial setting. You invalid dial setter, you. Hey, we just got a new dog! It's an Invalid Dial Setter!"
You can also receive special rewards if you defeat certain bosses with the dial at certain settings, as detailed below. Click through the individual rewards for more details.
References
- The dial alludes to a popular scene from the 1984 movie This Is Spinal Tap, in which the band claims they are louder than any other band, because their amps go up to eleven, which is one more than the standard ten.