Board Thread:Online Discussion/@comment-67.164.161.81-20150418181815/@comment-6881629-20150418192620

Some people have gone in had a hard time fighting the Sentinels so went back out to level and re-equip, when they came back the stone door that the first Sentinel opened had closed so they couldn't get back into the trials (maybe due to the area reset but i don't know).

Thinking about it you might be able to force your way though with the plate glitch on a console.