Diary

The Diary is a mechanic in Cookie Run: OvenBreak added in the Fabulous Pudding Cup Circus update. The Diary gives missions that you can complete for Diary Gems, that you can spend in the Diary Shop for various goodies. The Diary Gems and Diary Shop will reset with every major update.

The Diary was reworked into the Diary Calendar in the Feast in the Yakgwa Village update.

Missions
The Diary Missions are separated into three categories: The Diary Missions are separated into three categories: Daily, Weekly and Monthly. You can also get a reward after completing a number of missions in the mission category.

Daily Missions
The Daily Missions are three very simple and short missions: Open 1 Gold Chest, run in Cookie Trials 1 time, and run in Breakout Mode 1 time. The Daily Missions gives a lower amount of Diary Gems than the other missions, and completing 3 Daily Missions will give 100 Crystals.

Weekly Missions
The Weekly Missions longer than the Daily Missions, and will give more Diary Gems. The Weekly Missions has missions such as: Open 15 Gold Chests, receive Breakout reward 2 time, running 10 times in Guild Run, and use 100 Main Story Tickets. The Weekly Missions also has missions of event game modes, like Custom Runs. Completing at least 6 Weekly Missions will give 300 Rainbow Cubes.

Monthly Missions
The Monthly Missions are mission that are for the whole update, and will give the most Diary Gems. The Monthly Missions has missions like: Upgrading the two newly released Cookies & their Magic Candy to Max Level. Upgrading the two newly released Pets to Max Level. Upgrading the new Treasure to Max Level and reaching Diamond Rank in the newly released Cookie Trials. Completing at least 12 Monthly Missions will give you a Special Cookie Key.

Diary Shop
The Diary Shop is where you can spend your Diary Gems. The Diary Shop has 3 levels: Level 1 will always be unlocked, Level 2 will need 3,000 Diary Gems collected to be unlocked, and Level 3 will need 6,000 Diary Gems collected to be unlocked. The Diary Shop contains many goodies to purchase, such as: Supreme Cookie Chest, Supreme Pet Egg, 10+1 Treasure Incantation, the new and buffed Treasures of the update, Rainbow Cubes, Quick-Run Tickets, and sometimes even a Lobby Design.