In my opinion, the story of Doom Eternal is quite good. It has an interesting plot, intense action sequences, and well-developed characters that keep you hooked throughout the game.
The story of Doom Eternal takes place after the events of the previous game. Humanity is on the brink of extinction, and it's up to the protagonist to turn the tide. The game explores the ancient history and origins of the demons, adding depth to the narrative.
Well, Doom Eternal's story duration isn't set in stone. If you rush through, it might be shorter, but if you take your time and explore every nook and cranny, it could stretch to 25 hours or more. Generally, though, you can expect it to be around 20 hours for a typical playthrough.
One great Doom Eternal crossover fanfiction could be a crossover with the Halo universe. Imagine the Doom Slayer facing off against the Covenant. It would be an epic battle of different styles of combat and technology. Another interesting one could be a crossover with Warhammer 40K. The dark and gritty settings of both would blend well, with the Doom Slayer carving through hordes of Chaos daemons.
First, decide which universe you want to crossover with Doom Eternal. Then, research both universes thoroughly. For example, if it's a crossover with the Mass Effect universe, learn about the races, technology, and politics in Mass Effect. Next, create a plot that makes sense for both worlds. Maybe the Reapers from Mass Effect are interested in the demonic energy in Doom Eternal. Start writing, and don't be afraid to let your creativity run wild.
Doom Eternal does have a story element to it. The narrative adds depth and purpose to the intense combat. It's not just mindless shooting; there's a plot that unfolds as you progress.