(Nearly) complete OD&D Hack

So some time ago I posted a bunch of my houserules. Now it's time for the real deal that is the complete set of rules I use in my campaigns in lieu of the standard 3LBB stuff. It's heavily Chainmail 2ed inspired, and fuelled by long discussions with my fellow retrogamer Roberd (supposedly his blog is quite readable after machine translation so you can give it a shot) who happens to be playing in my campaign as well (and the other way around - I play at his table from time to time). 

After my trials with OD&D (around 150 games played over the last few years) what occurred to be is that the most significant element of the game is the Adventure, i.e. exploring both environments and events and watching the world unfold before your eyes (your meaning both the players and the referee, you know, this whole play to find out stuff). Thus the set of rules you need is required to provide fast outcomes to most conflicts. And since combat is the most common conflict (D&D stemmed from wargames, right?) the combat rules need to be adjusted to avoid the high-level slog early D&D becomes (combat as two potatoes trying to peel each other of their HP). 

The major amendment in my hack is ditching the seminal to-hit roll and Armor Class concepts and keeping the damage roll only. You may know the idea from Into the Odd and the games it inspired, my addition is however that the damage becomes massive on higher levels, so that late-game combat does not get bogged down and it still is resolved relatively quick. 

My design goal was also to allow using only one die type in all situations. And it works quite well - you'll need d6s only to run the game. 

Blogger is not a very good platform to publish sets of rules, so I post them here just for reference, the main document is available here (you can find the link in the sidebar on the right as well) and will be updated once every now and then. If I'll have enough time maybe some day I'll prepare a complete game out of it. As for now you still need the 3LBB to cover other game situations. 

Big thanks goes to my players of the Magic Sword campaign who patiently suffered under constantly changing rules and lost dozens of characters.

And if you're new to the blog and you feel confused seeing all this weird Polish shit be sure to check an introduction for English-speaking readers. 

(the picture is Vinternatt i Fellene III by Harald Sohlberg which quite accurately conveys the type of feel I like to have while playing old D&D)

COMBAT

Initiative

• Commanders of both sides roll d6+Loyalty Base (as per table on p. 11 of Volume I). If there is no commander (wild beasts, constructs, etc.) you subtract 2 from the result of the roll. 
• If the commander is a Hero, add +1 to the roll. Add +2 for Super-heroes and Wizards. 
• In case of a surprise the side which is not surprised performs movement, spellcasting and missile fire while the other side can’t until the next round. Melee is unaffected, however surprised characters have to fight with what they had in their hands during the ambush.  

Movement

• The side which won the initiative (rolled higher) starts the combat by moving their figures up to their Movement value. 
• If two figures are within their range they are in a melee. Unless: (i) a figure has initiative, (ii) both sides agree, or (iii) a figure successfully rolls a Saving Throw, when a figure withdraws from melee it receives an additional hit from all figures engaged in such melee. 
• The side which lost the initiative roll moves their figures up to their Movement value (pay attention to potential melee).

Spellcasting

• Unless a surprise occurs all characters cast their spells simultaneously (you can have each caster secretly write down their choice).
• The spells take effect in the following order:
• Staves
• Wands
• Other items
• M-U spells
• Cleric spells
• If a caster was dealt damage in the previous round, she needs a successful Saving Throw to cast the spell properly. If the Save fails, no spell is cast but the spell slot is lost.
• A figure engaged in a melee may cast a spell but does not deal any damage in that melee (receives damage normally however). 

Ranged combat

• Check the table below for determining effects of missile fire. 
• Each hit deals a die of damage, AC is not subtracted (since it’s already included in hit determination).
• A figure engaged in melee may shoot but does not deal any damage in melee (but receives damage as usual).
• A figure engaged in combat may freely use a thrown weapon in the first round of combat (before melee is resolved). 
• Thrown weapons cannot be used outside of melee. 
• All shots are fired simultaneously. 

Melee

• All hits are dealt simultaneously and no roll to hit is required (each figure deals damage).
• In case there are more than 2 figures involved each combatant declares how she distributes the hits between enemy figures.
• Each figure deals damage equal to half of their HD (round down, apply any pluses accordingly), so e.g. a Swashbuckler (HD 5+1) deals two dice of damage plus one.
• Magical weapons add damage dice equal to their magic level, so e.g. if the Swashbuckler wields a Magic Sword +2 she deals four dice of damage plus one pip.
• If a figure employs a long weapon it deals damage before the enemy (unless armed with such a weapon as well) in the first round, but in subsequent rounds the tables turn. 
• Two-handed weapons allow the player to roll an additional damage die and discard the lowest result.  

Post-melee

• If a figure was not involved in melee, did not shoot or cast spells - it may move once more up to their Movement value. 
• If a figure was knocked out it rolls a Saving Throw. If it fails the roll - death is imminent. 
• After every action is resolved a new round begins with a new initiative roll. 
• After the combat is finally resolved the figures which were not knocked out may shake off the damage and roll half of their HD, round down, adding their level and restore such number of HP. If a figure was knocked out but not killed it regains consciousness with 1 HP.

Optional rule: individual initiative.

• Each player figure rolls a die and adds their DEX bonus (3-8: -1; 9-12: 0; 13-18: +1). Result of 1-3 is a failure and 4-6 is a success. 
• A success means that such a player figure acts before the enemies and a failure - after the enemies.  

Armor class

Unlike in the original game, AC is deducted from non-magical damage dealt to a figure in combat by each blow. The value of deduction is the following:

Armor employed	AC
Leather armor or shield	1
Leather armor and shield or chainmail	2
Chainmail and shield or plate armor	3
Plate armor and shield	4

A helmet should be included in each suit of armor (for simplicity: just increase the price of all armor by 10gp). 

Magical armor adds its bonus to the protection (so a character using leather armor and shield +2 has AC 4). Magical armor protects from damage from magical attacks as well. 

After each adventure the armor needs to be tended by a skilled armorer in order to be usable in further adventures. The cost of such treatment in gold pieces is equal to the AC provided by such armor.

In case of monsters you can determine the AC based on their armor class value as set out in Vol. II. For simplicity and to show the power of most potent monsters you can also use a ruling that a monster's AC is equal to half of its HD rounded down (so a 7 HD monster would have AC 3). Or you can just make up AC for each monster - it could be quite refreshing to encounter a monster with high AC and low HD from time to time (be careful however, combat with such opponents may become tedious as they are not easily damaged and they do not do too much damage themselves). 

Ranged combat

I use the Chainmail 2ed. system (Missile Fire table from p. 8). Each HD of a character represents one soldier firing. Armor categories are dependent on AC and are as follows: Unarmored: 0, Armor or Shield: 1-2, Fully Armored: 3 and more.

The table goes like this:

Number Firing		AC 0		AC 1-2		AC 3 and more
	Die roll	1-2	3-6	1-3	4-6	1-4	5-6
1-2		0	1	0	0	0	0
3-4		1	2	0	1	0	0
5-6		2	3	2	2	0	1
7-8		3	4	2	3	0	1
9-10		4	5	3	3	1	2
11-12		Roll any excess as a separate group.				1	2
13-16						2	3
17-20						3	3

Each hit deals a die of damage. Magic bows and arrows add their score both to the damage dice when a hit is scored and to number firing value.

Magic-Users are free to employ crossbows.

Saving Throws

I’m not particularly fond of the original saving throw system so I employed my own, Chainmail inspired. There is one ST value for each class, a player needs to roll two six-sided dice equal or higher than the target number. Use the same target number for each effect a character is trying to avoid. 

LVL	F-M Target number	M-U Target number	C Target number
1	10	10	10
2	10	10	10
3	10	10	10
4	9	10	10
5	9	10	10
6	8	9	10
7	8	8	9
8	6	8	8
9	6	8	7
10+	6	7	7

Additional notes:

• Clerics add +2 to throws against effects caused by characters of opposite alignment (a Neutral Cleric does not have this advantage). 
• Magic-Users add +2 to throws against spells and spell-like effects (e.g. petrifying gaze of a Medusa, but not against a bite of Medusa’s asps). 
• For monsters I usually use the F-M table, however sometimes another one is more appropriate (e.g. a Lich should use the M-U table). 

MAGIC

So called vancian magic can be really annoying, so my proposal is that the characters do not need to memorize spells, they can freely cast any spell they know. Within a day a character may cast the number of spells of each level equal to the number of their corresponding level slots (as per tables on pages 17-18 of Volume I). Additionally any caster may use their higher level slots to cast lower level spells. For example a Conjurer (M-U 3) can cast any 3 first level spells and any 1 second level spell within a day or she may cast any 4 first level spells. It works much like in the fifth edition of the game.

I’m not really a fan of spell inflation starting from supplements to the original game, there are simply too many spells and most of them are not very useful in an open game. I like to keep it simple, so I only allow the spells from Vol. I with the following additions and variations (some as a natural result of combat variations):

• Magic-User can employ a first level Magic Missile spell which deals one die of damage plus the caster’s level and has a range of 240’.
• Sleep spell works on only one character of HD lower or equal of M-U’s level and there is a Saving Throw allowed.
• Charm spells work more like a Jedi mind trick and do not cause complete bewilderment as in the original game (Hold Person causes complete paralysis however). 
• Protection from Evil spells add +1 to Saving Throws and provide 1 point of magical armor. 
• Cure Light Wounds heals a die of hit points plus the caster’s level.
• Bless adds +1 to morale checks and one additional hit die when dealing damage in melee.
• Cure Serious Wounds heals two dice of hit points plus twice the caster’s level.
• Slow/Haste spells half or double the Movement rate of figures accordingly and allow withdrawal from melee without additional hits (an opponent of a Slowed figure may withdraw freely, so does a Hasted figure). 

Each spellcasting character knows the number of spells equal to their level and gains new spells automatically as they advance in levels (player chooses the spell). There is no spell learning, so each player needs to pick the spells wisely. If it sounds too harsh - assume that each spellcasting character knows three spells of each level.