At the time of finding the information, there would only 45 minutes until the next event would happen. It seemed the necklace didn't let the user become invisible, or even intangible. The necklace was an item that was dropped when a Shapeshifting Dragon was killed, and the amulet was filled with the Magic from the beast. The name of the Amulet was, blandly named, The Amulet of Illusions. It allows the caster to create illusions of their will, though only those with strong enough wills can use the amulet. People driven by their emotions have been known to be great users of the amulet, especially those of anger. But it usually leads to the person seeing things that aren't actually there.
Others have seemingly used the necklace in sheer fear or panic, and those people usually come off without any side effects.
And there is only one record of a person using it for good, and that was the first Hero who got the item, before it was passed down to his child, and then stolen, being lost for some time. The man who used it to help others had been a great warrior and known as the '1000 Man Army', due to his illusions.