I fear I've lost some of the details, but I had this completely awesome dream last night... In retrospect, it's a bit less coherent than it was at the time, but with a bit of spackle and some duct tape it fits together just fine.
Stage One was venturing out in the wake of some sort of disaster to get people to safety. A bridge had collapsed, or maybe exploded, so being unharmed and on a bicycle let me get people out of immediate danger to where emergency services -- or what was left of them -- could triage them, or just move the relatively intact ones back to the safe area.
Stage Two was trying to move around in this kind of post-disaster setting, which meant switching over to gathering batteries -- very sci-fi looking batteries -- moving quietly to avoid threats. Somewhere in there I stumbled across a big alien spider-monster just as some bad guys -- raiders? enemy soldiers? alien invaders? -- caught up with me from behind, with the result that I decided that getting out from between them was the priority, and ran away.
Which promptly turned into a hoverbike chase scene, and somewhere in the middle switched over to Stage Three.
Stage Three was full-on video-game mechanics, where I had to remember how to swap weapons, reload, return fire, etc... all while racing back to the safe area from Stage One. Definite learning curve even in the dream, but it was very cool. I even remember halfway-waking up long enough to think that I'd have play more of this later on, and then being kind of pissed that the game doesn't actually exist in real life.
All of which was a vast improvement over the dream from a week or so earlier, where "my family" -- not actually my family, just a bunch of random people who were my family in the dream -- had gone to a sort of waterpark/nature preserve... where they (we) murdered somebody for some inheritance. And of course one of the cousins screwed something up, and had to hide a body on the fly instead of disposing of it as planned.
This led to the nightmare sequence when I'd realized that the body had been found, there were investigators on the scene, and I was trying to grab my stuff and get off the property. Meanwhile my "parents" were insisting that everybody needed to stay calm and act normal and the cops definitely wouldn't figure out what had happened. And then getting out was incredibly difficult, since the park perimeter was blocked off, as were the areas around the rides, and... yeah. All for a murder that I hadn't wanted to be involved with in the first place.