After running the Red Box adventure, I downloaded a short encounter that was set immediately afterwards.  “Kill the Messengers” was brief, but I wasn’t looking for a long adventure for time’s sake anyway, and one encounter, some roleplaying in the city, plus my first homebrew fight would be plenty for one evening.

Let Cool Villains Get Away
Cheesy as it might be, I found the name of the evil necromancer in “Kill the Messengers” very cool.  Nynga Murdergrave just rolls off the tongue, doesn’t it?  Unfortunately, the fight, as written, is very similar to the last battle in the Twisted Halls: a necromancer plus some undead cronies. I decided to reskin the opponents; the necromancer turned into a zombie, while the skeletal rider became an evil warrior, in the same vein as the anti-paladins of 1E, with the sweet name.

The battle was quite interesting.  My players made excellent tactical use of their powers, and soon they surrounded Murdergrave.  Certain that they would defeat her soon, I decided to end the conflict early by letting her escape.  I improvised that the evil warrior drew some dust from a pouch, threw it on the ground, and the PCs were frozen by a burst of cold.  Then, Murdergrave rode off, sure to return in a later adventure.

Letting a villain get away is a good practice, for several reasons.  Speaking from a purely mechanical point of view, an escaped villain means a shorter encounter.  My old school sensibilities prefer shorter fights, and this battle had already gone quite long, especially with a table full of new players.  But the story-based reasons are probably more compelling.  When an escaped villain returns, it gives a sense of continuity to the overall plot of your campaign.  It fills the world out for your players, making it more interesting.  From now on, they might suspect Lynga Murdergrave is behind unusual events in their adventures.  An escaped villain is just one more tool in the box for a DM that can be used in order to make the game better.

Start Small with Homemade Encounters
It had been almost twenty years since I created my own fight, so I was quite nervous and worried that I would screw it up somehow.  The PCs had obtained a mysterious vial of green liquid in the previous adventure, and I wanted to create an encounter that began the first time they attempted to open it.  They decided to get the vial checked out by a wizard in Fallcrest, the central town in my campaign.

The vial itself was magical, with the same basic properties as a bag of holding.   Inside was a green slime which had been altered by necromantic magic.  When bloodied, the slime would split in half, and when each of these halves was bloodied, they would similarly split into minions with one hit point.  All individual slimes shared the same stats as the original.  I felt like this would make for an interesting, challenging, and memorable encounter.

In reality, it was far, far, too difficult.  New to the system in 4E, I hadn’t foreseen how tough the fight would be.  I had the characters using a map with the interior of a tavern, as it was the closest thing I had to a wizard’s shop.  The space was quite confined, and the mage and shaman had issues getting line of sight on the slimes.  My front line fighters were badly hurt, one falling to zero hit points, and it was only with the assistance of the NPC wizard that the slime was defeated.  I got the feeling that my players were quite frustrated by the fight, and found it both annoying and overlong.

The lesson to be learned here was hardly new, but still important: keep it simple.  The splitting effect as well as the cramped quarters ramped the complexity of the fight to a level that was not fun for me nor the players.  A standard green slime would have worked far better.  If the group had dispatched such a slime more easily, they likely would have had a better time.  The fact that it popped out of a small vial was interesting enough to make it memorable on its own.  As a DM, I can see that I have a tendency to overdo it, and in this, my first homemade encounter, I went way overboard.  I suppose most DMs are the same way.  We need to remember that sometimes, it’s better to keep it nice and simple.  There’s a time and place for creativity and innovation in my campaign, but it’s definitely after I have a few more sessions under my belt.