Time Stop is an epic battle item. All enemies lose 100% mana and have their normal attack delayed by 3 turns.
Time Stops are generally crafted in the forge.
Can also be received as loot from:
Due to the high cost, Time Stops are best reserved for powerful bosses, especially where you do not want their special skill to trigger. For example, many players viewed time stops as essential for preventing Mother North from reviving other enemies during the hardest levels of the 2018 Santa's Challenge Event. Although you can use Time Stops for titans, the limited amount of time that you have for a titan battle makes them cost prohibitive - except, perhaps, for high level rare titans.