The Broken Clock Tower is a Time-Limited Dungeon where players can farm a generous amount of Anvils that are used to strengthen the hero’s equipment. Every week, players are given a Time Limit Dungeon Key that can be collected in the player’s Inbox (usually sent after the weekly scheduled maintenance). Up to a maximum of 10 keys can be accumulated and kept.
Using a key will unlock the Dungeon for 24 hours. Once used, up to 5 floors of ascending difficulties can be cleared. On your first entry, you will need to clear the first floor so you can unlock and move up to the next floor. You can then repeat and clear any floor up to 15 times in total.
More rewards can be claimed the higher the floor, but the difficulty becomes significantly harder as well. Since it is a time-based dungeon, it is highly recommended to farm the floor where you can efficiently collect more Anvils at a given time. Battles also cost stamina to participate and the consumption is halved during the SP Dungeon half-stamina event.