Clock

The Clock, also known as Magical Clock, is a contact-activated object in The Legend of Zelda that can appear anywhere. If a clock appears and Link touches it, all of the enemies in the room will freeze in place, allowing them to be dispatched with ease. The clock does not affect enemies not on the screen, and once Link enters the next room, all enemies will unfreeze; moreover, the clock's effect does not have a time limit and will stay intact until Link leaves the room. Link does not get hurt even if he touches the frozen enemies.

The Shadow Prince
In The Shadow Prince, the Clock makes another appearance, serving the same function as in The Legend of Zelda. By moving the small knob left of the numeral XII, the clock will halt time for anyone except its bearer, but as soon as both hand knobs reach XII, time will go back to its normal pace.

The Clock is first introduced in the book when Impa gives Link the clock after the young hero decides to wait and not confront Charles of Moria. The Clock is not used in the book unless Link accuses Charles of being evil without having any proof to back it up, in which case he will be sent to a jail cell in the Tower. He uses the clock to halt time and proceeds to utilize a toothpick to push the cell key out the keyhole; afterward, the young hero slides a paper under the door to drag the key back in, which he uses to unlock the door just as the clock is about to return time to its normal pace. Link then quickly heads out the door.