Talia started talking to Keith about the Midnight Guardians pack and how they are in a different realm that can be accessed through a portal.
Keith had a question that was burning him since he found out about that pack, "How come no one discovered the portal?"
"They tried.", Talia responded. Axel was telling her about it when she was there. "Portal is surrounded by a natural maze and traps. Paths are enchanted to lead you away from it and energies are preventing electronic devices from working properly. Due to the terrain, the only way to reach it is on foot and unless you know the way, you will find yourself walking in circles. And even if you are right in front of it, you might miss it. It's fantastic, you will see."