Outpost ally lock out expoit
The Outpost construct can be abused to dig a claimed tunnel around an ally's dungeon, locking him inside it. I just tested it against Mira, and I successfully blocked her from the gold shrine and a underworld gateway, if there was no the cut scene I think I could even try to block her from her first gateway.
Game Version:
Steam Public
Platform:
Windows
When you are allied with someone you need to trust him.
There are a plenty of other ways to damage your ally and preventing them would limit the ways to help each other a lot.
So this is not a bug and changing this would bring more drawbacks.