You can obtain Gem Sockets every day by clearing the Daily Dungeon.
The jewelry sockets grade increases with stage difficult, and the number of entries is renewed every 00:00 hours. (3 times a day)
■ Daily Dungeon
① You can select the stage you want. (After clearing the previous stage, you can proceed to the next stage)
② You can check the number of entries.
③ Use the 'Dungeon Skip Ticket' to receive immediate compensation.
④ If you tap on 'Enter' you will use one ticket to enter the dungeon.
Basically, the Daily Dungeon is a single map type dungeon. Monsters that fit in the Dungeon appear by day.
⑤ You can check the progress of the dungeon.
⑥ You can progress the dungeon battle using Auto Battle.
⑦ When you clear the dungeon, the next stage will be opened, and you will be able to receive the Gem Sockets.
※ The guide was produced in a separate test environment.
So, It may change depending on the update and development situation.
Thank you for your love and interest in the Devil Book~
Devil Book Team