So we ventured into the ruins in search of the larger gate, and immediately found ourselves facing a huge collection of zombies and skeletons of various sorts. This was basically the boss fight, except that instead of an individual boss, we were facing one large mob.
The undead noticed us immediately and moved to attack. So did a dozen or so animated statues. Even worse: Some of the zombies were acting as low-level clerics or wizards. Our sorceress was taking out large blocks of enemies with fireballs, but our fighter took a lot of damage from Magic Missiles, and it was really looking like we weren't going to make it until the bard made us all invisible. That lasted just long enough to heal the fighter a bit, and then suddenly the bard was visible again.
The skeletons and zombies swarmed him, and he let them. Our sorceress released another fireball and killed the entire swarm, but took down the gnome bard along with them. (My elvish rogue/ranger was also caught in the blast, but he has Evasion and took no damage from it. Picture him brushing a bit of ash off his shoulder.)
With the bard dead, everybody but the sorceress was visible again. I moved to attack one of the zombie mages, which were the biggest danger. The fighter got close enough to the sorceress that she could make him invisible. Chasing the mage put me up on an overlook, and since I was the only one still visible everything came towards me... until I killed the zombie mage and tumbled off the side of the ledge, landing in a spot where the sorceress could make me invisible as well.
Hers was a better class of invisibility. With it in place, we could attack without becoming visible. Our fighter turned into an unseen meat-grinder, while my ranger/rogue moved off to hunt zombie mages (and quaff a healing potion, because ouch). The sorceress used fireballs and magic missiles to pick off the remaining targets, including a couple of the zombie mages and skeleton archers, while the fighter downed the last of the Dead Knights.
Invisibility was the only thing that saved us. The bard was dead. My rogue/ranger and the fighter were both fatally low on hit points. The sorceress was mildly wounded, but if the rest of us had died she probably wouldn't have lasted long. But with the skeletons destroyed and the zombies unable to see us, we were able to clean up.
That was when the the Solari showed up. Danathir, one of the desert elves, an elite warrior-scout in service to the Baron, had been missing for months. He appeared as soon as all the dead things were put down, to warn us that the Colonel -- who we rescued from a bandit camp after the initial raids, way back at the beginning of phase 2 of this campaign -- wasn't himself, and hadn't been since we'd brought him back. Naturally, we suspected a trap.
Unfortunately, we were wrong. The Solari convinced us to hide, and we did -- taking shelter in a passage behind a secret door, with a view overlooking the big room we'd been fighting in. That was when we (essentially) dissolved to a cut scene: the air shimmered, and the Baron appeared along with the Colonel and two of the Baron's Solari: a monk who served as his bodyguard, and the mage who teleported us out to the ruins in the first place.
The Colonel took a quick look around, pronounced the ruins amazing, and then the wizard cast a spell... that utterly failed to get past the magic resistance that a human colonel absolutely shouldn't have had and obviously did. He looked at her, and then cast Finger Of Death; she died. The other two moved to attack, but he stunned them with a word and slit their throats. There's a character I'm missing here, because the Baron was still alive; the Colonel said he was going to leave him alive to see this.
Then the Colonel activated the gate, and troops started marching through -- giving them access to the country well past the border, if they can find a way out of the ruins.
The Solari who had urged us to hide had a gem that the wizard had given him as a last resort. It could carry four people. Fortunately, there were only three of us left. So he crushed it, and teleported us all to the capital to warn the king.
We have a couple of choices at this point. We could make yet a third set of characters, and explore things from the side of the Elvish rebellion that our original characters set off. We could move to alternating between the two existing parties. Or we could create a single party from the existing two -- with each of us choosing one of our two characters and sticking with it. Personally, I'd like to see the Elvish side of things (and, of course, I love making new characters -- I'm intrigued by the idea of an Elvish Barbarian just now) but we're going to try to hash this out online before the next time we meet. Since that's going to be a couple of weeks, hopefully we'll have time to get things settled.