You can now pick up a copy of Doom II RPG for your iPhone or iPod Touch for $4.

The game includes nine maps, three playable characters, more than a dozen weapons, 11 enemies and plenty of upgrades. Game dev Zenimax, aka id, say there's about eight hours of gameplay tucked away in Doom II RPG.

Here's there official description:

A mysterious distress signal calls your team-two hardened Marines and a rookie scientist-to a Union Aerospace Corporation research facility on Earth's Moon, but you were unprepared for what awaits you. The forces of Hell itself have taken hold of the station and its inhabitants! Zombies and demonic monsters roam the halls, killing all who cross their path. Your backup squad is dead. Mysterious scientists conspire against you. Even the facility's AI cannot be trusted. You are being hunted from all sides. Now, you must fight to survive, and try to stop the invasion-and uncover the truth-by any means available. The fate of all humanity is at stake!

Ample gameplay for fans of Doom and their take on role-playing games, but I think I'll give this a pass. I enjoyed Wolfenstein RPG, but I'm not sure there's enough new here to attract me to another mobile RPG.

Doom II RPG Now on iPhone

Doom II RPG Now on iPhone

Doom II RPG Now on iPhone

Doom II RPG Now on iPhone

Doom II RPG Now on iPhone