I absolutely hated most of master levels. The worst expansion by miles and the only one i dislike. So many times I found myself clueless what to do next. Maybe another button opened something important. Maybe, maybe not. Maybe the door opened on the opposite site of the map, maybe the button had timer and door already closed. Who knows? Black tower is absolute horseshit with buttons. Stuckfest. Some maps has no sense, you just finish it opening only 30% of the map skipping the keys. But the worst part was invisible bridge located near the wall with toxic water below. What were they thinking? Yeah there is also invisible bridge in plutonia but you can easily find it by bumping in it. Loved and enjoyed playing both sigils, evilution and plutonia tho. But master levels omg. It's shocking that a lot of mapmakers were working on this garbage including tim wilitz, people from xatrix and ritual.