The average Doom playthrough usually takes between 10-15 hours, depending on the difficulty and how thoroughly you explore the game. On the easiest difficulty setting, you can generally get through the game in 8-10 hours, while the hardest difficulty setting can take up to 25 hours to complete.
Exploring the Game:
Exploring the game is a major part of the Doom experience, and it can drastically increase the amount of time it takes to finish the game. While some levels can be completed relatively quickly, others may require a lot of time spent searching for secrets, exploring for collectibles or trying to take out enemies in a particular way. Taking the time to explore the game can be hugely rewarding, as you’ll be able to find hidden weapons, power-ups and easter eggs.
Difficulty Settings:
Doom has multiple difficulty settings, ranging from “I’m Too Young To Die” to “Ultra-Nightmare”. The difficulty setting will affect how long it takes to finish the game. Playing on the lowest difficulty setting will make enemies easier to kill and will reduce the amount of damage you take, allowing you to complete the game faster. On the other hand, playing on the highest difficulty setting will make enemies more powerful and will increase the amount of damage you take, making the game much harder and taking longer to complete.
Multiplayer Mode:
Doom also includes a multiplayer mode, in which you can play against other players online. This mode can drastically increase the amount of time it takes to finish the game, as you’ll be competing against other players who may be more experienced or better equipped. It’s also worth noting that playing in multiplayer mode requires an internet connection, so you’ll need to be connected to the internet in order to play.