Overview

Each campaign mission hides a big secret—a map from the original DOOM or DOOM II. Once discovered in the game, the full map becomes playable. Select your campaign save slot and then click Classic Maps to see the available levels.

Look for a mechanical lever concealed in each mission. Often well hidden in the environment, accessing the lever may require completing an action before it is revealed. Once found, pull the lever to expose a new room containing a portion of the Classic Map. Enemies and resources are frequently found inside as the full level becomes available at the Classic Maps menu. Finding these secret areas contributes toward a Weapon Upgrade Point.

The maps are identical to the original games, but the enemies and your weapons come from the modern game. Your goal in every mission is to reach the exit, whether that’s a switch or a symbol on the ground. This may involve finding a color key or two to open the corresponding color doors.

Instead of dropping their weapon, the monsters release resources similar to the main game. Perform Glory Kills on them to gain extra health. You do need to worry about the z-axis in this game; shooting straight ahead will not kill a demon above or below.

Use your double jump to reach ledges that are normally out of reach. You can also reduce the damage taken in toxic areas by double jumping your way through. Do not underestimate the barrels. If a group of enemies wanders near one, detonate it, but make sure you’re at a safe distance.

Discover the locations of all 13 Classic Maps and how to unlock them.