What was the first dragon (or other powerful monster) your character slew?

I’m pumped for this one, because I actually did kill a dragon! Despite having played DnD since the mid 90’s, though, my first dragon kill (at least in DnD) was about four years ago. It happened toward the end of an exceptionally long-running online campaign that started a week or two after 4e came out. My character, Blordik, was a truculent survivor of a dwarven battlemage. He refused to learn any fire magic, because fire was for flashy, foolish, short-sighted children. Originally I’d planned for him to focus on force magic, but as the character (and 4e) developed he turned into more of a storm mage who dabbled in planar…well, not travel exactly. He tended to boot the souls of the party’s defeated foes into whatever afterlife they’d rightfully belong; since we were playing a converted Red Hand of Doom campaign, there were a lot of humanoids who’d turned to Tiamat from whatever god was traditionally theirs.

After several years of play, several changes of the PC guard, and a few cancellations/restarts, the party had cut a swath through underlings, generals, and a demon or two. They were crossing a great stone bridge which was, of course, defended by hobgoblin archers. Suddenly, green dragon. I assume the green dragon was from the actual adventure path, though I know the excellent DM running the game was making constant tweaks to keep up with the party. Originally I believe the theory was that we were to cross the bridge, destroy it, and then throw ourselves into the teeth of the army while buying time for reinforcements to dig in and fight the horde. Unsurprisingly, that was largely Blordik’s plan, as I decided that his outlasting so many fellow soldiers and adventurers had made him pretty fatalistic, but also resigned to his likely success in any endeavor he refused to give up on.

The dragon and his troops attacked us, and Blordik used two dailies to set up a pool of grease along the bridge that fed directly into an Acid Mire spell. That basically removed any threat from the hobgoblin soldiers, while still allowing our forced-movement-resistant soldier (technically one of Blordik’s utility spells given sentience, which ended up being a very neat way to bring another player into the game as a metallic doppleganger of the wizard who was convinced he was the real dwarf) to walk around smashing prone foes. Once the hobs were dispatched and the archers sniped from their watchtowers it was just the dragon, but that fight wasn’t going super well. The dragon had range, reach, and mobility, and kept swooping beneath the bridge to hit us on our flanks. We were mostly holding actions to hit him when he showed, but that’s a war of attrition that favors the dragon every time.

So I reasoned that several rounds of acid bubbling away at the bridge should, logically, have weakened the stability of the structure.

So Blordik began Thunderwaving the center of the bridge, pouring Action Points into it, and timing the final blow (Dungeoneering being the method he used to estimate this) for right as the green dragon flew beneath him. The plan went off great, thanks to some assists from the rest of the party (both in distracting the dragon with some potshots and in hammering away at the edge of the bridge) and we basically threw a bucket of dice at the dragon, then a second bucket when several tons of stonework caused it to crash to the ground in the chasm below.

After spending an hour or so climbing down into the chasm, Blordik instructed the party to sever the dragon’s head, which the PCs carried back to the nearest town. Later, agents of the dragon attacked the party, reanimated the head, and forced them into a fight in the woods that was considerably more difficult than killing the dragon the first time. I’m talking kobolds here, but that fight was brutal.