This campaign will use, as its base, the Old-School Essentials ruleset created by Necrotic Gnome; it is essentially a prettified and clarified version of the D&D Basic/Expert rules. While the (gorgeous) PDF version of the rulebook is available for $20, the rules are also available on their wiki. It is suggested that you familiarise yourself with, at minimum, the pages on character creation, your preferred class, and the rules on combat and exploration. I chose OSE for this due to its relative simplicity and clarity, hoping it will prove quick and easy for everyone interested to grasp. These kinds of games don’t have rules for every situation, and have occasional ambiguities, so in this document I will outline relevant interpretations and house rules. My goal is to adhere to the spirit of B/X, including embracing many of its particular quirks.
Setting
This campaign is currently set in the world of Mystara, an old setting created for the Basic line of D&D. The first mission was set in the Duchy of Karameikos, in the town of Stallonford, where the party was tasked with rescuing a goodly priest and then clearing out a foul necromancer who started this whole mess for his own reasons.
The second mission saw the party exploring a crystalline cave in a patch of enchanted woods, being intrigued over the rumour of a possible necromancer being spotted hauling bones into the cave. However, it ended prematurely with the characters abandoning it after a number of close shaves.
From there, the party chased rumours of a distant kidnapping to the small town of Caoilainn, and thence to the abandoned keep at Cormac’s Crag, where they hope to rescue several nice maidens.
For this campaign, please refrain from using Chaotic characters.
As an aid in making characters that fit the setting, I’ve also drawn up a very brief set of characterisation notes.
Clarifications and Personal Rulings
Characters and Levelling
Character Generation
Character stats will be rolled with 4d6k3; that is, rolling 4 dice and dropping the lowest score. Your scores will be pooled, and you will be permitted to assign them as you please.
At present, all of the core classes are permitted (including the demi-humans), as well as a number of additional classes I’ve backported and tweaked from various sources, though the latter are presently considered experimental and may be subject to change.
The optional rules regarding Encumbrance and Weapon Damage are in effect. Note that this means subsuming “adventuring gear” into 80 cn worth of weight; just mark that as part of your backpack capacity.
All characters with a non-fighting function will be permitted to begin play with the tool(s) needed for such, such as thieves’ picks, a holy symbol, or a spellbook. Replacements will need to be procured as usual. Similarly, a basic set of clothing and boots are also assumed, but need not be recorded.
Levelling Up
Demi-human levels will remain as-written, given the overall lower level cap for Humans given for normal play.
No more than one level may be gained per handout of XP; excess XP will stop at the threshold of the next level.
Combat
Missile Attacks
Strength bonuses on hurled weapons is a bit of a grey area and could be read either way. I will adapt the clearer Rules Cyclopedia ruling that it applies to all hurled melee weapons, applying the listed Damage bonus. Later on, I may put up special, and very expensive, bows that can make use of the Strength bonus as well, if desired.
The book phrases it a bit ambiguously, but I am going to rule that missile attacks are not possible if any potential opponent is within melee range, not merely the one you’re wanting to hit.
Non-Permitted Gear
As this isn’t explicitly covered by the books, I’ve decided that characters attempting to use a weapon not permitted by their class will be penalised as follows:
Attacks will be made at -3 To-Hit.
Crossbow attacks will be made at -2 To-Hit instead, as they’re designed to be easier to use.
Dwarves and Halflings simply cannot use too-large weapons; it’s too awkward to manage.
Clerics run the risk of being penalised by their deities for so doing, as it violates their oath.
Clerics will be unable to cast any further spells on the same day an edged or piercing weapon is used, at minimum.
All such weapons must be abandoned as soon as the combat is over.
Similarly, characters attempting to use forbidden armours will be penalised as follows:
Armour AC will be halved, rounding down.
Scouting/sneaking checks (cf. “House Rules: Exploration”) will be penalised as though the armour were one category heavier, with heavy armour in such a case resulting in guaranteed failure.
Movement rate will be one category lower.
A shield will be ineffective against missiles and only assist with one attack per round. Magic-Users will be unable to cast spells, and Thieves will be unable to do anything requiring both hands.
Magic-Users will not be able to cast spells in armour.
Thieves cannot use their abilities (except linguistic) while using medium or heavy armour.
Stealth
A Thief’s backstab attack will not work against monsters with 360° vision or a lack of discernible anatomy.
Exploration
Light Sources
Light sources may not be held in the same hand as a shield unless the shield is a buckler (cf. “House Rules: Items and Equipment”). Naturally, this applies to users of two-handed weapons as well. Given that Clerics are able to cast normally with a shield and weapon equipped, and given that the rules on casting spells do not discriminate between either type of casting, I will permit arcane casters to work magic while holding a torch, with the assumption that their dagger or staff is sheathed or otherwise out of the way for that round.
Items and Equipment
Miscellaneous Item Clarifications
10’ poles are assumed to be collapsible to the width of a backpack and may therefore be secured above one when not in use.
Missile Clarifications
Weapon weights subsume one full stack of ammo.
All missile ammo is assumed to weigh 1 cn per unit independently.
Sling stones are infinitely available on-site from most locales, but you will be limited to a maximum of 20 stones per encounter unless you intentionally gather (and track) additional stones.
Do not alter the weight for missile weapons even if you’re out of ammo; think of the first stack as “free”.
Weapons don’t come with ammo when you buy them.
Although not mentioned on the in-game price-list, silver-tipped quarrels are also available at 7 GP each, extrapolating from the listed prices.
Salvaging and Selling
Regular arms and armour found on enemies are often of poor quality, especially for non-human/demi-human foes, and thus not suitable for looting. Items which are salvageable may be used or sold for half of the listed price, rounded down.
Magical items cannot be sold, as there’s little to no effective market for them (high risk), but you may be able to find other uses for them, such as handing them off to hirelings or using them in barter.
Items not known to be magical, however, will be sold at their apparent value and XP granted accordingly.
Shield Clarifications
Shields cannot be used with two-handed melee weapons. With the exception of a buckler (cf. “House Rules: Items and Equipment”), this holds true for two-handed missile weapons as well.
Mages and Magic
Arcane Spell Acquisition
A new character entitled to arcane magic may choose his guaranteed first-level spell freely; any bonus spells (cf. “House Rules: Characters and Levelling”) will be rolled for randomly. Subsequent spells guaranteed by the class-chart can be gained for free once per level via mentoring, but such spells will also be rolled for and the tutoring will take one week of game time. Alternatively, specific spells may be obtained via magical research, or, in certain circumstances, negotiation with a relevant person who can teach the desired spell. Any combination of such may be done to fill out any available class-chart slots. Bonus slots are not filled out via mentoring beyond the initial starting selection; these must be tracked down in-play.
Only spells in your book can be memorised. Spells in captured books do not count as yours.
Rulings on Select Spells
Floating Disc
The disc will always endeavour to remain at waist-height, but can follow a caster vertically. Otherwise, going over hills and such could be problematic.
Phantasmal Force
When “attacking” with Phantasmal Force, monsters will attack using the caster’s THAC0 and do “damage” corresponding to their type. Faked magical effects will use their normal values.
House Rules
Characters and Levelling
Character Generation
At this time, I will not permit PCs with a gender opposite the player’s in order to avoid anything getting weird, especially for those new to role-playing.
Class Adjustments
The Magic-User and Cleric classes will be amended to have a minimum Attribute requirement of 9 in Intelligence and Wisdom respectively.
Magic-Users will be permitted to start with Read Magic in addition to their normal limits; it’s just too crippling not to have.
Arcane casters will be permitted to have additional spells in their spellbook for each spell level per level equal to the number of bonus languages their Intelligence score entitles them to. This does not alter their castings per day, but rather their spell availability. For example, a first-level Magic-User normally has one first-level spell in his spellbook (in addition to Read Magic), but one with 13 INT would have three (for a net gain of one) to choose from, but may still only cast one per day.
Divine casters will be given extra spells per day (starting at levels 2, 4, and 6 as applicable) based on their Wisdom modifier. A character who gets a bonus will have that many extra first-level spells; if a lower-tier bonus is listed, that applies to second-level spells, and again to third-level spells at 18 Wisdom. Thus, 3/2/1, 2/1/0, or 1/0/0 extra spells.
The Fighter (and thus Knight and Paladin), Dwarf, and Halfling classes will be given the “Cleave” ability: if a melee attack kills or incapacitates an enemy, the character is permitted to attack a new valid target in range with the same weapon, being allowed to move up to 5’ between cleaves, provided his movement per round has not been exhausted. This may potentially be done a number of times equal to the character’s level. For example, a first-level character can kill one monster and thus gain only one free attack, even if the second attack kills another monster; were he instead a second-level character, he would then be able to attack a third time.
Elves and Foresters will also be permitted to use this ability, but are treated as a Fighter of half of their level, rounded down, reflecting their divided training.
Halflings and Halfling Burglars may, on a tied initiative roll, move first, being treated as a separate side.
GP, XP, and Maintenance
Critically, we will be departing from the normal ruleset regarding XP as follows:
1 GP is still worth 1 XP and is still affected by Prime Requisite bonuses. However, in order to get that XP, you have to “spend” the GP directly as such. This will be subsumed into your monthly expenses, which in practicality means your inn/basic living fees “off-screen”, training fees and/or materials, presumed equipment maintenance, and your character’s “downtime” entertainment. Adventurers like to live it up.
An active character who has reached the level cap will be expected to “spend” 100 GP per level each month in expenses, in addition to wages due hirelings. In practice this is 800-1400 GP depending on class. Failure to pay this will result in various penalties to be determined by the DM relative to the deficit and circumstances. By that level though, this should really be a non-issue, especially if you are in control of a Stronghold, which generates taxes.
This carries with it the implication that money not actually gained as “treasure” in the usual sense may be spent. That is largely correct, but the DM reserves the right to intervene in the interest of balance if necessary.
Money can only be spent on XP immediately after character generation or when combat XP is handed out by the DM. A PC’s spending during this time can bring him only to the threshold of the next level.
With the exception of a level-capped character at the end of the month, spending money on XP is optional; you can hold back money if you have other needs at present. If there is uncertainty, spending may be delayed until after shopping, etc. within a reasonable timeframe.
HP Minimums
All level 1 characters will be permitted to begin with a full hit dice worth of hit points; this is before any alterations due to Constitution, and only applies to level 1.
Characters reaching level 2 or beyond who are due an additional Hit Dice will be allowed to re-roll on a result (after applying Constitution) of less than either 2 (for classes that always get full Hit Dice) or whatever that class would get when they no longer get full Hit Dice. For example, a Dwarf can never gain less than 3 HP per level and a Halfling never less than 2 HP per level. A Magic-User can still be stuck with 1 HP.
STR Bonuses to Carrying Capacity
For convenience, I will implement STR-based bonuses to carrying capacity. To use it, add or subtract the relevant amount from your total weight before consulting the encumbrance chart:
Strength
Adjustment in cn
3
+300
4-5
+300
6-8
+100
9-12
0
13-15
-100
16-17
-200
18
-300
Combat
Additional Manoeuvres
I will implement three additional combat rules, mostly as an encouragement to aid tactical behaviour:
Charging in melee: Once per combat, a character may execute a charge attack, which works as follows:
The character must be able to move at least 20’ in a mostly-straight line; this is a run, and as such full movement speed may be used instead of the encounter speed.
The character gains a bonus of +2 to their To-Hit roll, but a penalty of 1 to AC until their next turn.
Weapons that can be braced against charging monsters are also effective against charging characters.
Disarm: In lieu of a damaging attack, the character may attempt to disarm his opponent by successfully rolling to hit the target, who can save his weapon by rolling a Dexterity skill check (assumed to be 11 if not otherwise specified). The weapon used to disarm must be of equal or greater size than the target’s weapon.
Dual-Wielding: Characters with DEX and/or STR as a prime requisite may choose to wield two one-handed weapons; the secondary must be of small size, like a dagger or hand axe. When so doing, attacks are made at +1, and the natural number of the die determines which weapon strikes on a hit: odds are the off-hand, evens the main hand. In the case of a natural 20, the most damaging weapon of the pair will be used (usually the main hand).
Force Back: In lieu of a damaging attack, the character may attempt to shove his opponent backwards by successfully rolling to hit the target, who must then make a saving throw versus Paralysis; if the attacker is significantly larger than his opponent, the save is made at a -4 penalty. If the save is failed, the opponent is knocked back a number of feet equal to a normal damage roll by the attacker. If this causes the opponent to hit an obstacle, he takes 1d6 damage for every 10’ he travelled. If he hits another character or monster of similar or greater size, he is knocked down (see below); however, if the struck person is smaller, that person is knocked down instead and the opponent continues to be forced back.
Helpless opponents may be dispatched immediately if the attacker is not engaged in melee with other opponents.
Knock Down: In lieu of a damaging attack, the character may attempt to trip, sweep, or otherwise knock his opponent down via succeeding on an attack roll at a -4 penalty; the opponent must then save vs Paralysis to keep his feet. Failure results in the opponent going prone. Attacks against a prone opponent are made at a +2 bonus, and backstabs are possible if an eligible character is not otherwise engaged in melee. A prone opponent stands up again the next round in place of movement.
Overrun: Characters may attempt to get past an opponent without fighting it by succeeding at a normal attack roll with a -4 penalty; if it hits, the opponent must make a saving throw vs Paralysis, gaining a -4 penalty if the character is significantly larger. If the opponent succeeds, the overrun fails and damage is rolled normally, otherwise, he is bypassed and the character may continue moving as usual. A successful overrun does not count as an attack.
Parrying: Characters with 13 STR or above may forfeit their attack for that round, instead applying their STR bonus to melee attacks as an AC bonus for the duration of that round. This may be combined with a Fighting Withdrawal, but not a Retreat.
Grappling
Grappling is not defined in OSE whatsoever, but I have come up with the following approach:
In order to grapple, you must be unarmed.
Against an opponent with a weapon, except when surprised, the opponent will attack first.
A successful hit does no damage, but deflects the grapple attempt. The opponent may attack “for real” immediately after if they have not yet attacked that round.
If the attack is not deflected, or if the opponent is unarmed or surprised, do a Strength check; apply a +1 penalty for each HD the opponent has over the attacker and vice-versa. If successful, roll 1d2-1 damage and consider the target restrained.
All damage is subdual. Upon reaching 0 HP, instead of the usual surrender, the opponent is knocked out.
A KO’d opponent can be dispatched as per the Sleep spell.
A KO’d opponent will wake up in 1d6 rounds and gain 1 HP per round until coming back to their previous non-subdual HP total, sans any actual damage suffered from then on.
On the opponent’s turn, repeat the Strength check in order to maintain the hold. Losing allows the opponent to break free; he may then act as usual that same round.
While the hold is maintained, the opponent takes an automatic 1d2-1 per round, but both the user and opponent are unable to take any other actions.
If a hold is instead dropped voluntarily, the user can act as normal that same round.
A grappled opponent can be attacked by a third party like a stunned opponent (automatic hit in melee).
General Combat
When making an attack roll, an unmodified (natural) roll of 20 will cause the given attack to automatically do its maximum damage unless such a roll was necessary to hit in the first place. This applies to enemies too!
Firing into melee is not expressly forbidden or penalised by-the-book. However, I will modify the roll as necessary to account for cover or positioning, which is basically by-the-book, and on a roll of 1 I will rule that the shot goes astray and is aimed at an unintended target, chosen randomly within plausibility; this may include multiple potential characters depending on circumstances. This unintended shot will be rolled normally.
Firing over a dwarf, gnome, halfling’s head is possible provided you are not one yourself; otherwise, anyone in front of you will count as some degree of cover.
Another element not covered in the rules, but which I believe to be sensible, is allowing spears and polearms to be used from behind an ally, though at -2 To-Hit from behind humans or elves, -1 from behind a dwarf, or with no penalty from behind a gnome or halfling, assuming a human-sized character. For dwarves, it’s -3/-2/-1, but for gnomes or halflings, it’s -4/-3/-2.
Player HP Cushions
As a bit of a cushion, a character with a Constitution of 9+ is considered knocked out at 0 HP and may suffer additional damage equal to their HP bonus (thus 0-3 additional points of damage) without dying.
Healing effects treat HP as 0 in this case.
Characters who recover from this are immediately able to adventure; no downtime is necessary.
Post-battle, a character may bind their or another’s wounds in order to recover 1d4 HP, provided said HP was lost in that particular battle. Each character may only benefit from one binding per battle.
Swapping Gear
Given the short combat rounds, I’d like to handle weapon and gear swapping as such:
Switching between melee weapons and non-hurled missile weapons, or switching between sword-and-board and dual-wielding, takes up one round, including removing or re-equipping a shield.
Switching to a designated secondary weapon carried on the belt is “free”, including a weapon intended to be hurled.
Switching from a weapon to a holy symbol in order to cast spells or turn undead is “free”; it is assumed to be drawn again at the start of the next round. Same deal for Magic-Users.
Dropping a weapon and then drawing another, including missile, and vice-versa, is “free”, but it takes one round to retrieve and stow such an item afterwards.
Grabbing anything from inside your pack takes up one round; you cannot use the item until the next round.
Exploration
Hunting
Taking some inspiration from The Heroic Legendarium, I will adjust hunting as follows:
Hunting still takes 1 day of no movement and cannot be combined with a rest day.
The party may split into multiple groups, each with their own 1d6 roll for success as well as their own 1d6 roll for a wandering monster encounter.
If successful, the 1d6 roll for food will supply the entire party that amount of fresh rations.
Foraging will remain the same: 1d6 for success, 1d6 for that number of fresh rations. This doesn’t stack with hunting days, and cannot be done on rest days, but also doesn’t impede movement.
Usage of Thief Abilities by Non-Thieves
A non-Thief attempting to move silently or a non-Thief/non-Halfling trying to hide in shadows will make his roll as a first-level Thief, but medium and heavy armour will impose a penalty of -5 and -10, respectively, to the former check. This includes enchanted varieties, as they are lighter, not quieter.
Items and Equipment
Bucklers
Bow and crossbow users, as well as Bards, Halfling Burglars, Rakes, and Thieves, are permitted a buckler, which grants -1 AC, but strictly in melee, not against ranged attacks. Bucklers cost 5 GP and weigh 30 cn. Halfling variants weigh half as much. A buckler cannot be used with non-missile two-handed weapons, or when dual-wielding.
Money-changers
Money-changers can convert coins and treasures to various gems of 1 cn weight each (for a 5% fee) as follows:
Gem Value
Price
10 GP
10 GP 5 SP
50 GP
52 GP 5 SP
100 GP
105 GP
500 GP
525 GP
1000 GP
1050 GP
Mages and Magic
Captured spell books can be used in magical research if Read Magic is available. Using a book in this way decreases the cost and time of the research by 50%.
Scrolls can be used in magical research; a Magic-User scroll will require the use of Read Magic. Using a scroll in this way uses it up, but decreases the cost and time of the research by 25%.
Rulings on Select Spells
Shield
I will permit Shield to protect against Magic Missile if a saving throw is passed, as per BECMI.
Culture Shock and General Advice
A few bits of advice:
Don’t expect plot armour. I’m not trying to kill you, but I will not hesitate to do so if the situation warrants it. Dungeons and the Wilderness are hostile and actions will have consequences. Consider your alignment, too — holy men who act up will be punished accordingly.
Magic is complicated. If you’re allergic to complication, play a warrior-type character, or perhaps a Cleric.
If you enjoy hoarding, avoid the Forester or Mystic.
XP is assigned from both defeating (not necessarily killing) monsters and collecting and spending GP and loot, as detailed above. An exception to this is known-magical items, as the real reward is in keeping them. XP derived from fighting monsters is split among all surviving party members. Bonus XP may also be awarded for good role-playing, clever plans, or otherwise sufficiently amusing/impressing the DM.
To reiterate, it is not necessary to fight every monster. It is very possible to bribe or distract them, for example. Gung-ho hack-and-slash is often a very good way to get killed, or at least waste resources.
Magical items are not as easy to identify as in the computer games or later editions. Items can have obvious properties identified via experimentation, e.g. sipping a potion, using a weapon or set of armour in combat, or pointing a rod at something. Otherwise, it’s generally necessary to hire a higher-level NPC.
The dungeons often contain traps. Some of them are warnings, some of them may well try to kill you. Use common sense, and make good use of that 10’ pole and other miscellaneous tools.
There are essentially two kinds of traps: room traps and treasure traps. Dwarves and Gnomes can detect some of the former with their class abilities, as can any character taking appropriate measures, as suggested above. Treasure traps are the domain of the thief and rake, and generally cannot be role-played through, though sometimes they may be able to be bypassed by other means.
Hidden passages and doors exist, and must generally be found by actively searching a given area. Being reasonably specific in what you’re looking for (e.g. a loose brick or unusual books) may work out via role-play. Elves of any sort have an improved ability to spot these.
Some monsters can only be harmed by silver or magical weapons, so if you find an example of one, if your character can potentially use it, you might want to hang on to it.
It is necessary for your characters to eat and drink as well as sleep. It generally isn’t as big a problem as it might sound.
Being of more a simulationist bent, backpacks, sacks, pouches, and the like are needed to haul stuff around. Mounts help too.
Time is broken down into 10-second rounds, and 10-minute turns. Rounds are normally used in combat, and turns outside of it.
Initiative is rolled at the start of each round, and the highest number goes first. Individuals do not roll for initiative, as combat is assumed to be chaotic and nearly simultaneous in most cases. In the event of a tie, both sides will resolve simultaneously, meaning that there can be mutual kills.
Saving throws and attack rolls are “at or over”, and ability checks or percentile dice are “at or under”.
When levelling, and even from Level 1, take notes on your total HP. Some strong monsters can drain levels on a successful hit, and a side-effect of that is losing HP. Without notes, should you get your lost levels restored, you’d have to re-roll your HP for each regained level.