Well the problem seems to be pretty easy and in the same time very annoying. When i'm trying to get inside Lich Tower, i can't. There is no entrance and whenever i want to break one block some kind of green shield with mini-squares appears on the entire building/ section of building. A big shield that i can't penetrate but just in creative mod. And it wouldnt be the problem this fact if beside this i couldnt fight even the mods. I hit them but i can't make any damage, expet ofcrouse in creative. I don't know the problem and i really want some help. Also i don't have the FTB modpack installed i installed only the twilight forest mod. But i coulndt find any help on other sites so can someone explain and help me the situation? Thank you.