Hexen

Hexen, released on October 30th, 1995, and is the sequel to Heretic. The Hexen engine is based on the Doom engine, but uses an extended level format with more general linedef specials, with the same specials able to be executed by things upon death (monsters) or pickup (items), and z-heights can be set for things as well. It also has a basic scripting language called ACS and incorporates various ASCII lumps to which makes the engine more user-friendly and expandable than the original Doom engine.

Hexen also features a fully-functional hub system, which allows the player to move back and forth between maps as if they were a single large map.

Hexen, the game, has five hubs.

Hubs

 * Hub 1: Seven Portals
 * Hub 2: Shadow Wood
 * Hub 3: Heresiarch's Seminary
 * Hub 4: Castle of Grief
 * Hub 5: Necropolis

There is also a prologue map and an epilogue map, which are actually part of the first and last hubs, respectively, but due to the game architecture they can only be entered once.