Board Thread:Plants vs. Zombies 2: It's About Time/@comment-25928375-20150430085936/@comment-25089892-20150502131831

Actually, if no one noticed, this message pops up when you get free World Key.

"Hang on to your keys! You may need them for upcoming Travel Log quests!".

That does mean we may need World Keys for completion of some quests or what?