This is the second part of an adventure series where YOU determine the next step in the story. Read part one. Vote in the comments below or on Twitter at #TheMark.

You decide to avoid the gargoyles and search for another way in. You signal your team to fall back another 30 yards. A few minutes later, the team gathers behind the wing of a 757 that protrudes from the ground like a shark fin. You pull a map of the city from your bag and point at a remote spot at the edge of the airfield.

No one looks happy, but they seem to understand that it’s your best chance to avoid more human-demon hybrids.

You jog to the east edge of the airfield. Scraps of planes, service vehicles, and towers lay heavy on the ground and give plenty of cover. Halfway to your entry point your nostrils twinge with a familiar foul scent. Directly below you is the maze of ventilation ducts of New Milwaukee’s processing plants that turn thousands of pounds of cow dung into electricity and fuel. The processing center is only reachable through a narrow, methane-filled passage. The team has small oxygen packs that are just enough for a one-way trip. You’ll have to move fast.

You reach the service grate and bash open the rusted latch with a rock. Metal rungs descend into the shaft. Small ducts appear opposite of the rungs. You climb in first. The smell of manure turns your stomach.

At the 19th duct, you stop and hoist yourself across. The methane is thicker here, making you light-headed. You activate your oxygen pack and don the mask. Almost instantly, your head begins to clear.

You crawl deeper into the duct. While you wait for your team, you hear a skittering sound ahead, but you can’t tell if it’s coming from inside your duct. You remove your night-vision goggles, grab your flashlight, and shine it into the passage. About fifty feet ahead the passage turns left. The way is clear. You stash the flashlight back in your pocket and put your goggles back on.

The trek through the ducts is quick; you’ll even have a few minutes of oxygen to spare. As you near the end, the temperature rises dramatically, threatening to bake you in your body armor. The metal beneath you bends more easily under your weight. You must be over one of the processing tanks.

You signal your team to space out to keep from putting too much weight on the ducts. The soldiers in the rear hang back. As you crawl forward, the duct beneath you lurches. You realize you’re putting too much pressure on a seam between the panels. You start scrambling past when the panel beneath you gives way. You feel yourself fall through the air for a few terrible seconds, then splash into a large vat of thick and slimy material. Instinctively you grab your rifle and scramble to your feet. You hold the rifle over your head. An unlucky teammate is doing the same thing.

You’re both standing in waist-high manure. The walls are sheer metal except for a three-foot pipe that gushes manure into the tank on one side. The rest of your team is looking down at you from the mangled duct fifteen feet up.

You have enough oxygen to last another 25 minutes. Your team could haul you both out, but that would take a lot of time and most of your oxygen. Instead, you could crawl through the pipe of manure, though you aren’t sure where it leads. Either way, you could run out of oxygen before you make it to safety.

What do you do?

A: Have the team haul you up out of the tank.

B: Crawl through the pipe.

We want your vote! Vote in the comments below or on Twitter at #TheMark. Voting ends Tuesday night. The highest vote will be the next step in the story, posted on Fridays.

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Image courtesy of Matthew Harrison Blue.

Voting for Part 2 is closed. Thanks to all who participated!