I've been playing some form of Dungeons & Dragons (mostly 2nd edition AD&D, though I played and Dungeon-Mastered a few 3rd edition campaigns in my university days) since I was 9 or 10, when I visited my friend Mark and his older brother cracked out the "intro-to" boxed set (Silverleaf Halfmoon, anyone?). Although my pen-and-paper gaming has been on a hiatus for nearly four years, I finally got together a new group of adventurers and started DMing again at the beginning of January.
D&D is awesome for a number of reasons: killing crazy monsters, fighting evil sorcerers, finding amazing magical items, and hanging out with friends, for example. But I think the greatest part is the stories that come out of it. Although the DM is in some way responsible for structuring the outcome of a campaign, the reality is that, when everyone sits down at the table, no one knows what the result will be. Players react to the situation that the DM creates, and in so doing, change the way of the world around them.
For example, for our first session, I designed a dungeon that I thought the party could sweep through in a single evening. However, they took a cautious approach and ended up laying a trap for a sortie of monsters leaving the "abandoned" fortress at night. They ended up killing two important "sergeants" of the evil boss, without even stepping foot inside the dungeon - something I hadn't expected at all.
Then, for our second session, I had to rearrange the entire dungeon. The death of a whole slew of monsters at the hands of the party - including eight goblins, three hobgoblins, an ogre, and a handful of evil priests - meant that the "ecosystem" of the dungeon had changed. This made the boss fight a lot harder, because the evil priestess running the place decided to raise the ogre and a couple of the hobgoblins to fight for her in zombified undeath.
But that's the best part. The final battle became much harder than I had intended it to be, because of the actions of the party. But just when I thought everyone was going to die - and, consequently, develop a deep hatred for me as a DM - the one player left standing whipped out a mancatcher (essentially big metal mandibles on a pole used for dragging horsemen off their mounts), caught the evil priestess in a vise grip, and proceeded to squeeze her to death. It was both hilarious and - for the end boss I had lovingly designed - ignominious.
I can't wait for the next session. Although I have some work to do - preparing possible adventure hooks, designing some dungeons, thinking up new monsters for the party to fight - the fun part is that I have no idea what will end up happening. Storytelling is extremely fun when it's done together.