I explained to the players that their four neophyte wizards were members of a research team (employed by the Estates Arcanum) sent through a magical portal to explore an ancient fortress called "Dwimmermount." It was hoped that the characters might gather information about the wizard "Turms Termax" and his pursuit of immortality, rumors of which had spread across worlds.
The catch: Dwimmermount lay in another world, and while Divination revealed that the spellcasters' own magic would still function, the fundamental principles of native Tellurian magic were different and unknown.
I had the characters enter on level four and begin their exploration near the shrine of Saint Tennen and the mysterious blue curtain.
Over the next couple hours the young wizards explored a half-dozen rooms, often splitting up and constantly casting spells as they went until they began to lose hit points and experience side effects from "spellburn." Here are a few highlights:
- they Created a magic ladder of braided paper to help them investigate a glowing orb mounted in the ceiling
- When assailed by an animated, iron statue they managed to temporarily Transmute the iron into a flock of goats (one of whom was promptly named "Gerald")
- successful negotiation led to an alliance with a trio of strange little men whom the group dubbed "gnomes"
- realizing that they had neglected to bring candles, a small cloud was magically Created and then Enchanted to glow ... moving the cloud with the party remained a problem however
- a decision to stop and rest without posting a watch led to a character having both his feet dissolved to mid-shin by an ooze
- aggressive overcasting and poor luck on a side effects roll left one character turned to stone until such a time as she should strike the focus of her latest spell (a nearby block of wood)
... basically it fit with all the mad cap action I've come to expect from both middle schoolers and the open-ended magic system of Olde School Wizardry.
I had anticipated a bit of work on the fly to convert Labyrinth Lord to Olde School Wizardry, but there was almost no combat and none of the four PCs ever attempted a melee attack (not that they carried weapons anyway), meaning that across two hours of play I never really had to address the differences in systems.
If the wizards *had* tried to focus on hand to hand combat for some reason, I would have had to eyeball each monster's AC and decide whether points should be attributed to evasion or armor (armor is ablative in Olde School Wizardry, reducing damage dealt). I left monster hit points and damage dice alone. This would mean that B/X D&D goblins and similar low hit dice creatures would be slightly more fragile than their Olde School Wizardry counterparts (not a big issue).
The only really jarring difference would come when we compared NPC men-at-arms across systems. A standard fighter in Olde School Wizardry uses his CON stat for hit points and deals 2d6 with a melee weapon, making him roughly the equivalent of a 3rd level fighter in Labyrinth Lord, so had the party left the mountain and decided to tangle with the watchmen of Muntburg, for instance, I would have had to promote the lowest level guards by a couple levels (higher level NPCs would remain unchanged).
It was a successful little outing in any case and has left me pondering whether I want to use Olde School Wizardry or Labyrinth Lord when my weekly after school club returns to Dwimmermount in the fall.