Chapter 13: From Beyond in Doom: The Dark Agesputs the Slayer back atop Serrat, his trusty dragon mount. The Sentinel command station is under attack and the Slayer must fight back the demonic forces ...

Chapter 3: Barrier Core does not have any collectibles or secret areas to find. Players can get 100% completion for the level by simply going through the objectives in Chapter 3. Chapter 4: Sentinel ...