Since Devin was jonesing for some more D&D--at midnight no less--so we decided to through a few encounters in an effort to wrap up Keep on the Shadowfell. Having slain a dragon last session and returned to Winterhaven with word and proof of their deed, they ventured north towards the ruined keep in order to discover the source of the rampant arcane energies that Valthrun had sensed.
I'd drawn up a hasty foundation map with crumbling walls, shallow graves, and grim wards that would writhe and scream when closely approached. As the players investigated the ruins, ancient and armor clad skeletons rose from the ground and attacked under the direction of cultists. A few were dragonborn skeletons that could breath a life-sapping energy, stealing hit points and healing surges alike. After their destruction and a purifying prayer from Donner, they found a ragged suit of chain armor that protected the wearer from necromantic powers (subsequently donned by, well, Donner).
Within a ruined shrine dedicated to Erathis they, after much deliberation, descended into a dark hole with deposited them in a hellish catacomb wreathed in crimson light and glass pillars filled with screaming souls of the damned. Blood flowed from numerous alters, collecting in a deep bit that was guarded by more undead and cultists engaged in an unholy rite in the name of Orcus. Sand took the initiative (literally) by trying to backstab a skeleton, which didn't work out as well as it could have. Skeletons clambered out of alcoves and frenzied cultists hedged the party in, capturing them in a pincer attack. Other, physically inept cultists hung back and withered away the party's strength with magic.
This was a pretty grueling battle. Though I'd clustered the minions up nice and tight, Riven had a difficult time incinerating them. Donner's armor didnt help much because Sand was at the forefront, and it made the most sense to hit him instead of going for targets that he was granting cover to. Many rounds, action points, and healing surges later, they prevailed. Fortunately neither Donner nor Riven used their daily spells, because the fight wasn't over: the high priest was still waiting with a several tattered spirits at his beck and call. I called it for the night, since by then it was almost two in the morning.
I haven't gamed that late since I was in high school.