Good condiment, isn't it? Makes your hotdog taste better and your teeth yellow. Bet you didn't know it's made from a seed. Even if you don't particularly like it, we've all tried it at least once. Some love the taste, other people prefer ketchup, and there's also those people who mix the two, but that's beside the point. Mustard is good stuff, if you like it.
There is something, however, that the word mustard is applied to that isn't as nice, regardless if you like it.
I want you to imagine for me, that you're sitting with your friends outside on a cool fall night. There's a small fire going, you're making stew, laughing, joking, having a fun time, enjoying yourselves. You don't even hear the 'thud'.
You smell something familiar, a smell you know from somewhere else. Horseradish? Garlic? The meat you're cooking is seasoned, but you can't recall using either of those. There's a faint itch at the back of your mind, something about what a friend told you before moving to a further away sector, but you can't quite remember what it is. Ah, but who cares? There's meat cooking and you've got company. You push it to the back of your mind and focus on enjoying life. With warm bellies, a happy heart, and some friendly fighting over a card game going on nearby, you doze off.
You awake not a half-hour later, coughing. The smell from earlier is overpowering your nostrils and making your eyes water. You're having a hard time breathing. It's dawning on you what's happening. Gritting your teeth and wiping at your eyes, you reach for the thin chemical-soaked hood, pulling it over your head. It's itchy and reeks of chemicals, you can barely see out of the eyepieces, but you know that this is the best thing you have, and that it'll keep you safe. It's only now that you're noticing the thick yellow cloud enveloping you. Your friends are still asleep in their own bunks, or so you can make out through the yellow smoke.
But then, it starts. A pain growing on your hands. You rub at them, confused, but it doesn't do anything to alleviate your pain. In fact, it's getting worse, creeping up your arms now, soaking through your tunic. It feels like your body is being struck by thousands of pins and needles.
And then it really starts.
Your fingertips feel cold for a moment, the aching going away.
Hot. Your fingers feel so hot. Your hands feel like they're burning up, you look down and see through your mask and the smoke that there are already blisters forming, the bags of loose pus only aching worse on your hands. Your arms are succumbing to the fire. Your lungs feel like they're going to give, you're wheezing still, even through the hood. The meat in your stomach is turning, you feel like you're going to vomit, but you aren't sure why you can't breath at all now, your throat is closing up, so hot all over, skin heavy, lungs feeling like they're going to collapse, so sore, so much pain all over you, so hot, so sore, so painful, so sore
The pain lessens mercifully.
You wake up in agony. You're in a bed now, your uniform gone. You're breathing heavily through a throat clenching up, gasping for air. This isn't right. Whatever you breathed, it choked you and left you barely able to see for the watering, but now, you're begging for that again. Your skin is covered in saggy sacks, every inch of your body burning like a candle is being held to your skin at every conceivable point. You start to cough, gasping between them for the little air you can gather up, and see that you're coughing up liquid. It's red and it feels far too warm, you want more than anything to be submerged in a bath of ice.
Barely able to breath and covered with blisters, you remain in that hospital. It dulls, eventually, the pain tapering off into a dull ache, but the burning is gone. You're so relieved. The pain is gone now. You're told that you're going home and that you're lucky to be so, some even suggesting jokingly that you ought to thank the people who sent you the 'gift'. With the nightmare of whatever the hell that was behind you, you return home to your family.
But that isn't the end. A year or so later, you receive great news, it's finally over and the continent is at peace again. That's the good news. The bad? Your body isn't healthy.
It's killing you. Slowly. The blisters and your throat closing in? That wasn't the goal of the monster that attacked you that night, it was merely the short-term effects. It's eating you from the inside.
You're dying. You survived the cloud of yellow smoke, but you're dying. Cancer is killing you. Your body is filled with cells in active rebellion. Treatment is ineffective. You're given a timeframe of how long you have left to say your goodbyes before your body kills itself.
Good gas, isn't it?