Underground Treasure Chest

''Under construction. All text below is a translation of the information from the DMM Touken Ranbu community page.''

How to Play

 * The event The Underground Treasure Chest involves exploring the underground area beneath Osaka Castle and collecting Koban. To participate in the event, simply select the event banner from the sortie page.
 * Floors 1 to 50 are for all players to enjoy. By stepping on certain nodes and clearing floors, you will receive Koban as reward. The reward for clearing 50 floors will be the new sword Hakata Toushirou.
 * Floor 51 onwards will be the challenge stage. As the enemies become stronger, we recommend you challenge these floors based on the level of your team.
 * In addition, for players who manage to clear the 100th floor, a special present will be rewarded at a later date as a token of commemoration.

Others

 * Should you return to the citadel in the middle of a map, you will resume at the beginning of the floor you were previously at.
 * After clearing all 100 floors, you will repeat the 100th floor.
 * By defeating the boss on the 100th floor, in rare instances you will be able to obtain Hakata Toushirou.
 * There is no level limit for experience gain.
 * Kebiishi will not appear.
 * Hakata Toushirou will have special abilities that can be utilised in future events.

Hints

 * After defeating the boss on each floor, you will automatically proceed to the next floor. However, swords will build up fatigue per floor so please be careful. Since you cannot confirm the fatigue levels of swords during sortie, we recommend that you return to the citadel from time to time to monitor fatigue levels.
 * All maps within the event are day maps. Oodachi and Naginata have an advantage here, however having Tantou in your team will slightly increase the chances of stepping on resource nodes.
 * By clearing specific floors, you will be able to receive a variety of rewards, including, but not limited to, troops, items, etc.