This feedback update seems to have implemented Adventure Slot Key Z, which unlocks the 6th and 7th adventure slots. Up to now, there were a total of seven adventures that were five adventures. The adventure series will continue to be improved with various missions, making it easier to play, so it may be even easier.
How to get Adventure Slot Key Z
The adventure slot key Z×10 can be exchanged for 1000 Z medals at the Z medal exchange. The Z medal is an item that can be obtained when the character's Z power exceeds the maximum possession of 9999.
In other words, 1 Z-medals per adventure. It's a slight amount for old players and payers... I would like to use it carefully, such as those who have few Z medals only for long adventures. The seventh needs 100 to open...