Giant obsidian tower structure built within a lake of lava, not 100% complete yet.

This tower is a source of great evil power, it holds the key to the end and as long as it remains active the world shall forever be merged with the nether. Inside the tower there is a dragon chained in order to guard people from entering. A beam of energy originating form the "room of power" shoots from the third floor then goes through a filter corrupting it causing a rip between the nether and earth therefore merging the two realms. the bottom most level is filled with lava that flows from the river, this chamber holds the highly sought after dragon egg.