Back to the Future 1999 has officially been in public beta. Players can receive beta rewards in their mailboxes. However, many players do not know what conditions are met to unlock the mailbox. The following editor will introduce to you how to unlock the mailbox in Back to the Future 1999.
Play the main line to unlock, pass 1-4 to open the mailbox
It takes about 15 minutes to jump through the plot. Get the first ten consecutive items from the mailbox. You can draw them when you get to the initial stage. It’s not very efficient.
Skipping the plot and only pushing the main storyline takes about an hour to reach level 3, and about three and a half hours to reach level 5. After completing all three ten-company rounds, it takes a long time and is not suitable for the initial level.
The method of unlocking the mailbox in Back to the Future 1999 has been shared above. Interested friends can refer to this guide. I hope it can be helpful to all players. If you want to know more game guides and information, please continue to pay attention to the game on this site.