Two weeks ago, during the finale of fourthcore's M1: Gallery of the Hate Blossom, the PCs were running out of time and hp. I'd imposed a 4 hour real-time limit on the adventure, using the threat of an inescapable hoard of undead legionnaires answering the alarm of the demoness (known as Hate Blossom, a half-marilith/half-medusa lich). Presently waging war on some uncounted layer of the Abyss, seeking to establish Hate Blossom more permanently, it would take them 4 hours real-time [not sure what that amounted to game time exactly] to arrive and come to their queen's aid.
The party had been detected early on in the gallery complex, and they knew the hurt was coming, however the PCs felt they had plenty of time. With 3+ hours in your pocket, you would too...
Finally, after battling stone golems, tasting poisoned fountains, lying to trapped demigods, and bluffing an undead lieutenant, they found themselves in the midst of the last dramatic battle. The solo Hate Blossom still had 200 hp, and her general and lover, the death knight known as The Black Saint, wasn't even bloodied. A blackroot treant had also just entered the fray with some debilitating zones when the PCs realized they only had 15 minutes left.
The dwindling time limit was made even more poignant for the fact they'd run out of resurrection charges on their Amulet of Amon Rahvan (a home brew item which more or less gave 3 standard action raise deads, meant in the spirit of a tournament-style dungeon crawl and necessary for the fact 3 level 17s were attempting a fourthcore adventure meant for 5 level 16s). Ironically, none of the PCs ever actually died from challenges or conflict, rather were petrified by Hate Blossom's lethal gaze, and, unable to undo the curse without 10 minutes unimpeded time, the surviving allies thought it better to shatter the statues, kill their friends, and then bring them back from the dead. Oh, D&D logic... it worked, though, until they ran out of charges and their cleric bit the dust.
What happened then was the stuff of tabletop legend...
Through a combination of well-timed 20s, and the very last drops of their healing droughts, the fastest turns I've ever seen, and a clever epiphany by the dwarf: covering his eyes at the end of each turn as a free action and happily accepting the 'blinded' condition in the face of almost certain petrification (something the dead cleric kicked himself over and over for not thinking of), they got Hate Blossom down to 30hp. There was less than a minute left on the timer, however, and PCs could hear the undead swarming the outer reaches of the gallery, even begin battering and ramming the doors just outside the demoness' chambers.
One player, a mix-pact Hexblade, had what they all knew would be the final turn. In a whirl of description and dice-rolling befitting a master, he howled, taunted, cursed, and spun those dice, hitting, factoring bonuses, and JUST managing to get the last damage dice out of his hand before the time was up.
Now I was faced with a choice, end it there with a TPK failure, or actually listen as the player frantically added up his damage. I described the undead bursting through the doors and literally threw a handful of minis on one side of the map like Emril's BAM maneuver. Before I could even turn back, I heard a desperate cry, "Thirty-seven!?!"
I paused, looked him in the eye, began slowly shaking my head as all of them edging the table began to deflate. "You... kill her..."
I began a gory description, but I don't think they heard anything beyond 'her' as the trio started jumping around, high fiving each other, screaming all sorts of send offs to the demoness. Then they realized the horde had arrived, and in a true stroke of brilliance, the hexblade burned his AP, cut off Hate Blossom's unliving head, and aimed it at the vast crowd pouring into the sanctum. I had him roll a Hard Arcana check, which he made, then one, massive attack gaze using Hate Blossom's bonus, which he also made. The undead vanguard was turned to stone, providing a solid stone wall!
Again the players cheered, and managed to defeat the surviving Black Saint and Hate Blossom's bloodied treant apprentice Gutroot in another four rounds. Did they technically make the time limit? No, not really. Did they win the scenario? I'd offer a resounding yes. Did they have an awesome evening and place the finale on their shelf of memorable games? Totally.