Background/gameplay[]
The original Doom set the gaming world on fire when it was released, due to the controversy of its violent content, needing fairly high hardware requirements in order to run on most computers back then, and making the First Person Shooter into a huge gaming genre, increasing its popularity then.
The game involved a lone Marine investigating a distress call from one of Mars's moons, which the player (controlling the Marine) had to make their way through over a dozen levels, trying to stay alive while battling against a variety of creatures, ex-Marines and various other dangers, such as traps that could cause damage, if not death to the player. There was also a multitude of weapons and items for the player to pick up and use, along with ammo and several ways to increase a player's health and armor status.
There were also various secret rooms and a variety of functions needed for the player to utilize in order to open up more areas of levels (i. e. such as using keys, pressing buttons and flipping switches found in areas of the game) in order to make it to the exit.
The player only had one life, although they could save the game at any time, along with having five skill levels to choose from.
As far as the sequel of Doom 2 went, all the graphics, controls, and weapons were the same as the original, with only a couple of additions, such as the Super Shotgun being added and a Mega Sphere to increase a player's health and armor to 200%. However, the gameplay was widened by adding the ability to jump (actually the player couldn't physically jump, but there were many levels where they had to either jump or fall down a distance in order to make it through various areas) and by having several additional monsters added to the mix.
The Depths of Doom Trilogy contained the above two games in their entirety, along with many other bonuses. The package was developed by id Software and released by GT Interactive in 1997 for the PC.
The Depths of Doom Trilogy[]
This three cd set contained a lot of material, including the original Doom. There were a few changes made, like a couple of secrets were added, a few were totally redone, some levels had a few added graphical details to them, a crushing ceiling was added in one level that wasn't in the original, and the game ended on level eight after the player got past an enemy known as the Barons, as when the player entered the building behind the Baron area that originally would have the exit, the player would actually get warped to a hidden area where there was no way to escape and they would die there, as not even the invincible cheat mode for the Doom games would save the player. The game would have to be continued by manually restarting on level nine.
This package also included Doom 2 as well as 20 Master Levels that was originally released as an expansion pack to the latter, along with Inferno, billed as a sequel to Doom, as it lived up to its name, rather than going by the theme of a tough Marine forced to survive, as the levels were more supernatural-themed, containing macabre graphics, lava (the first level), demons and a creepy vibe in general (the grayish-black stalagmites in level two). Also included was Thy Flesh Consumed, which had a high difficulty level, as its first two levels didn't have much room to maneuver, yet there was a high level of bombardment from enemy attacks. Other levels were bigger but could have traps that would unleash many monsters from confined areas.
Finally, the majority of this release included over three thousand homebrewed levels collected from the internet. These really varied in quality, from being very easy to totally impossible to get through without using cheat codes, as the player can be put in a level with the most powerful monsters possible but with practically no chance at all of survival, due to these levels not including much in the way of firepower. WAD (as these levels are called) creators did all kinds of things as well, such as creating or using different music other than what was originally included with the Doom games (a MIDI version of "Smells Like Teen Spirit" from the band Nirvana adorned at least two levels on the release), using new graphics, replacing game sound effects with clips sampled from various entertainment venues (soundbites from the first RoboCop movie to the Beavis and Butthead TV show could be heard in some levels, among many others), or to having certain WADs not work at all, as several patches had to be made for the release.
Also, many WADs were repeated as well, since it would be a very difficult job for id Software and/or GT Interactive to keep track of them all, since many WADs contained several levels each, which the player could find many of these levels used over and over again as they went through the package.
Also varying in quality was the mixture of the types of levels included in a WAD batch, as the player could go through several levels of a batch with monsters and all to finding levels totally devoid of enemies, since there could be levels thrown into some batches that were Deathmatch or Co-op only, requiring other players simultaneously.