Are you sure because the end of the first one leads you to believe that the story continues right where it left off. The other 3 horsemen where on there way to earth as the 7th seal was broken.
Yeah, that's what I thought, but I'm quite sure (
Source: Joystiq). However, when you think about it, this makes sense.
Where were the other 3 horsemen while War was being framed? I presume if War was summoned, the other 3 have to be summoned otherwise they're the worst Horsemen of the Apocalypse ever. However, the whole mastermind plot was to use War because of his honor or some shizzle. The main character of Darksiders II was announced to be Death. I think it will take place mostly around the same time as the Apocalypse from the first (not a spoiler, it's the first scene) and a little of the time period between War's sentencing and return. There's a whole lot of time unaccounted for. It'll probably explain that scene at the end of the first that you referred to.
What I found odd though was that the final boss was the easiest in the whole game. I don't think he hit me more than once, and that was only because I miss-timed the kill button. But struggle to finish? No, I beat the game in about 6-7 days and I was into it the whole time. It's basically a M Rated Zelda and I don't see anything wrong with that, especially since I couldn't be bothered to finish Twilight Princess yet needed my Zelda fix. This fulfilled it and now I'm ready for Skyward Sword.
I struggled to finish because I was bored. It was really interesting in the beginning but when it finally hit that Vigil Games wasn't breaking any new ground, I didn't feel compelled to finish. I was already over halfway through the game so I willed myself through it. It was the same feeling with Twilight Princess. I almost didn't finish it because I was so bored by the time got to the snow/ice dungeon. The fetch quest at the end of Darksiders was especially tough to get through. I don't know why developers think that a fetch quest right at the 11th hour is a good idea and something that people want to engage in. "Oh, hell yeah! Final boss, here I come! Oh, wait.... I have to collect these 12 things? **** you, game." /excitement killer