It was the very start of a brand new homebrew campaign for me and my friends. Our thespian dungeon master was known for being tricky and cruel at times, but always in good fun. We understood she was just being theatrical and enjoyed every minute of it. The party was scattered and not all playing at the same time yet, so it was just me and one other player who was relatively new to the game at the start. He was playing a sort of hardy fighter, and I was playing as a spiritual exorcist. Being well versed in the game myself, I knew I could go off of my own without much trouble but wanted to stay near the newer player and help him get started in the game. We did the usual things most parties did at the start. Looking around at the setting, find a nice tavern, and try to find some quests. I of course get the first one, a ripped page of a notice board that we never really did go back and finish. All standard DnD stuff. We got a npc fire lizard on our side wthin minutes but the new player was taking it slow so we didn't really go anywhere with this at first. When it came time for a break, the DM and I decided to speed things up and get me an early first quest in so that progress could be made. So we of course walk around and the first thing I run into is the local thieving syndicate. It was a pretty basic job; steal back and item someone else had stolen. The item in question was a magical staff, so right away I was cautious about who might have wanted it. I was still at bare bones on my character, having no spells and only a dagger to my name. But I took the quest anyway and off I went with a time limit and location but little to nothing else to go on. When I arrive at the described place it is a simple farm house with no lights on in any of the windows. I figure that this 'farmer' would be more than he seemed, and I was more right than I ever wanted to be. After sneaking around and nearly getting caught by the farmer who exited his house, I track him into his shed where he disappears after I look in. Naturally, the idea is to look for a trap door, which was easy enough. But once I went down, things took a slight turn for the worse. This guy had dug tunnels underneath his shed and had a couple of rooms down there with signs of blood and water. I nicked the staff and got my quest done, but there were still some scrolls and documents I wanted to come back for when I wasn't under a time limit. Unfortunately, the farmer spotted me down there the second time around and I had to fight my way out. Our DM that game allowed us to learn new skills by trying new things in the game, so I creatively tried to use his severed third leg as duel wielding a weapon and surprisingly it worked. I killed the farmer, got the duel wielding skill to boot, and made it out of there with the goods in hand. I ended up getting a Light spell and some money as my reward for the mission, but this tale does not end there.
After a few more session and the complete party now at the table, five of us including a half Reaper warrior who loved scythes too much, the newer player trying his hand at any and all combat styles he could get his hands on, an odd acting tank who just ate anything in sight, a charismatic mage, and myself the exorcist. We were getting a hang of things and had fell into a lot of gold via a mimic chest and decided to go spend our newfound wealth around the town to help us advance. This shopping episode included the purchase of the local library which the Reaper set up as our main base. But after looking around our newfound home, we discovered a door leading into the basement. The library caretaker, whom we had kept on to run the public part of the library, told us never to go down in there. Of course, we ignored him and went down to investigate because this is DnD. You NEVER leave a door unopened in DnD without good reason. This is one we should have. The DM was making it clear that this door led to a dungeon which we were far under-leveled for. Of course, we kept going in, but cautiously. We meet a couple of badies in the first few rooms, but the more we go in the bigger it gets. Even though the library was huge above us, this basement was even bigger than necessary and I did not like where it was going. At one point we find a room with the floor covered in blood and the signs of ritual all around. Naturally knowing how my DM is, I tried to use my spiritual senses on the room. Basically like a detect evil spell. What I got back from the DM was that the entire room was filled to the brim with the souls of children and infants all trapped there in a bunch, all around us. I immediately express the want to leave to my party, knowing that this would not end well. Of course, we continued exploring, but I had to put that option in their heads just in case retreat was necessary.
The final room in the dungeon was a large double-doored entrance and inside was nearly pitch black as we walked in, weapons in hand. Eventually what appeared to us was a 12 foot tall demon looming in the darkness, with the same eyes as the farmer I had killed at the beginning of the campaign. At once I realized my mistake, but it was too late. The initiative had been rolled and the doors locked behind us. The demon was mocking us here and there, casting spells, and swinging hard. Nothing we didn't expect, but for some reason, he went after the Reaper more often than not. I thought it would clearly go after me first, being the one who slew him earlier. But I guess Reapers and Demons didn't get along on this world. The battle was hard fought and won, but we were battered and nearly dead. Crawling back up into our library to lick our wounds, I considered sealing the basement or maybe even performing an exorcism down there for all the children souls that were still trapped, but we never got around to doing so. But we learned a valuable lesson none the less: Do not treat NPCs with disrespect just for being NPCs, it may come back to haunt you.