Wait, it dosen't have to equal 0? Making changes if so...
The modificators, I mean.
It can be less, but it can't be more. (An earlier train of thought would have let the bonuses exceed the penalties by two, but I decided against it.)
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Five people appear in this place, a strange place.
One is "Archmage Coolguy," a clever and powerful man whose physical abilities are a bit less impressive. His wand is a delicate wand of walnut wood, just over eight inches long. The journal he possesses has seven pages filled with compiled notes for coming here, leaving 43 for any notes he wishes to take. He, being the first to arrive, takes stock of his surroundings.
The floor is smoothed natural stone, but the walls are masonry of the highest quality. While no mortar was needed to hold the perfectly-fitted walls in place, it is clear that this place was dug, and then walls were put up. It is also improbable that the walls would come down. The walls of these chambers have glowing spheres of cool magical light, but the corridors seem to be unlit. Speaking of corridors, there are two archways leading south and one leading west; an occasional sound of large scurrying legs sounds from the western passage. It is an eerie place.
Just as Coolguy starts to wish he had someone else to be here--just to acknowledge how cool he was, of course--Javier C, a somewhat frail and rather foolish young man with a hardhat and an aura of power, appears. Javier has a stout mahogany wand, almost 9.5 inches in length, and a diary containing 7 pages of notes and a compiled map of this whole place. His journal also contains a cryptic note he'd found: "Find the biggest centipede for fame or doom." Javier glances sideways at the archmage, in his violet runes and stiff fedora, but before he can question the Archmage's sanity or existence another form appears.
With a pop and a thud, Jane Schandles appears about a foot and a half above the ground, before striking the smooth stone floor. Her journal is stuffed into a large pocket in her cargo pants, while a multitool and a smartphone share a smaller one. Jane is weak of body but mighty of mind. A teak wand, 18.4 centimeters long and fairly dull, is gripped in her left hand, while her right holds a scratched and only slightly rusty crowbar. Jane checks to make sure nothing is broken; then, with some help from Javier, she stands up, a bit shaken, a bloody scratch on her cheek clotting.
Soon, Jane is joined by a younger girl. Clair Hatter, a little girl with as much strength as a grown man, as much innate cleverness as all her teaches combined, and as much toughness as a sick bunny rabbit, poofs in in a burst of orange dust. Her wand, nearly a foot and a half long and made of polished rosewood, is clutched in one hand, with a violet umbrella in the other. Clair grins and looks around, her grin fading when her eyes fall on the Archmage. Suddenly, this doesn't seem to be like such a fun tea party.
The last to join the "party" at this time is Meus, a 30-year-old who is already starting to suffer from joint pains despite his innate hardiness. He and Tattletale come out of one of the southern arches, then spin around, surprised to find that they are not where they were. His simple clothing cannot conceal the dagger at his belt, nor does sticking his teak wand and the Elder's book in a sack make it any less obvious that they are on his person. He spun around again at the sound of scrabbling legs, to face four others. Strange characters were they, one in robes, a little girl, and two in stranger clothing. The Elder's book was correct; a strange place this is!
The five looked at each other in apprehension...and eight big centipedes, the size of serpents, crawled past Meus!