So we were on pl_frontier. A fairly fun map. Lots of well thought out chokes, lots of juicy flank routes for both defenders and attackers, nice long sightlines for snipers but short enough that they were still vulnerable and unable to hold alone.
We steamrolled through the first few checkpoints, then hit a pretty major roadblock. A new sniper had joined. This one had strange killstreak Australium weaponry, all with tens of thousands of kills recorded on them, as well as a rather expensive unusual. At a glance, he was wearing the equivalent of about $200+ USD of cosmetics and skins.
He effortlessly held off our team alone, with almost totally perfect accuracy. THe team's steamroll became a push, became a trickle, became a stalemate. We'd reached a point where we couldn't proceed because to push the cart meant death faster than we could react. Naturally, this player became cocky and arrogant, started trash talking in chat. He had certainly gotten some very suspicious headshots, but top tier snipers are about as accurate as him anyway. He'd gotten to an 18 kill streak (20 = "godlike") when I came up with a stupid plan.
I dropped two stickybombs down on a blind corner that he couldn't hit me from, while a medic overhealed me to prepare for the damage the jump would inflict. (This is that portion on Frontier, just after the second last point, where there's a series of concentric steps climbing upwards.)
Now at full overheal (260), ready to jump, I gave myself a second to prepare. I knew the vague direction the scary enemy sniper was in. I knew my jump would land me within spitting distance of his entire team.
I took a breath, crouch-jumped over the two stickies, and launched myself into the stars, flying at high speed. The stickies had done a lot of self damage, but the overheal cushioned most of that, so I was at about 140hp. That's within the danger range for a headshot kill (<150).
I see the sniper look up at me, see me flying in rapidly. He takes aim.
He misses, and backpedals to try for another shot.
Still in motion, i swap to my Loch n' Load, a grenade launcher that breaks on impact, but travels faster than the stock launcher which explodes on impact and after rolling. They now deal the same damage, but the Loch is easier to land a shot with due to its higher speed.
I fire the pill. It oneshots the sniper, because of his secondary (Darwin's Danger Shield) causing him 20% extra damage vulnerability to explosives. From full health he would've survived that, but he was evidently grazed by something (DDS snipers have 150 hp, and a loch pill would deal 120).
I land, take the fall damage, and immediately taunt. The entire enemy team arrives and blows me up, but it was so, so worth it.