Quote from: Larsdangly;832992OSR style systems best fit the following criteria:

- Genuinely compatible with most or all pre-3E and modern OSR materials (i.e., it is D&D, not a separate game inspired by D&D). For example, DCC is awesome, but really doesn't fit this criterion.

- Thief abilities start at first level at a level of competency more similar to other things in the game (e.g., the ~50:50 odds of most people's attacks in combat).

- There is some sort of central task resolution rule or rules, so it is obvious how you are supposed to resolve things other than combat or class-specific abilities.

- Your stats significantly impact your abilities.

I will shamelessly suggest my own game. See link below. At least, it fits your requirements.

Quote from: VectorSigma;833026That said, if you go with 5e, you will want to make a pass to tweak hp totals in an older adventure.  5e PCs can put out some damage.

Just double the hp, add attribute bonus to damage (usually +1 to +5, default to +2), double attacks or damage dice if high level, and you're pretty well sorted.

I solved the Thief issue by treating their %s as akin to 1e Magic Resistance - "this is your chance vs an 11th level threat, +/- 5% per level above or below". So that's eg +50% to sneak up on typical 1 hd critters. Suddenly Thief becomes a pretty cool class. The Thief IMC is awesome - admittedly she has nearly died twice so far, where no one else has come close.

Quote from: S'mon;833054I solved the Thief issue by treating their %s as akin to 1e Magic Resistance - "this is your chance vs an 11th level threat, +/- 5% per level above or below". So that's eg +50% to sneak up on typical 1 hd critters. Suddenly Thief becomes a pretty cool class. The Thief IMC is awesome - admittedly she has nearly died twice so far, where no one else has come close.

I've often wondered if the Thief's high saves versus various magical effects weren't a direct influence from the Fafhrd & Grey Mouser stories; even though he was a low-level magic user himself (statted as a 3rd? level magic-user? I think), Grey Mouser was extremely cynical about magic and tended to disbelieve just about everything supernatural he saw.  Indeed I recall a story where the two miscreants intended to re-enter Lankhmar and were almost immediately set on by various foes including a magic-user wielding a death spell which Mouser turned back on him by using a copper wire to ground himself and channel the energy right back, evoking an idea that Mouser knew it was "merely" lightning...

The best suggestion I've seen here is Fantastic Heroes and Witchery, which is more complex than what I had in mind, but definitely covers all the bases I suggested, and much of the extra details are really very creative and fun. It is sort of like DCC re-caste as something within the D&D fold.

It also provides a nice illustration that the grognard purist arguments about what does and doesn't constitute an 'old school' style game are generally a lot of bullshit. It is not heresy to clearly state what sort of die roll is appropriate when someone tries to hide or jump or whatever. FH&W is a decidedly OSR game, and generally works within a uniform approach to dice rolling mechanics.

Earthdawn. Every roll is made on the Step Table (dice pool list) & 4th edition cleaned up the resolution mechanics very nicely (no more chart lookups for resolving success levels). All stats are generated on a 3-18+ scale, and then converted to a Step # which makes up the base of all skill/talent/spell rolls vs Physical/ Mystic/ Social Defense ratings (also calculated from the 3-18 stats).

Best of all, here's a First Circle Thief in the 4th edition rules -IMO, the best expression of an OSR thief out there (f you count "can summon telekinetic lock picks" as 1st level as every Discipline in Earthdawn uses magic):

Half-Magic: Thieves may use half-magic to build or bypass security measures intended to prevent theft, and to recognize different types of locking mechanisms.
Free Talent: Danger Sense (free, rank = level, spidey sense, roll vs trap initiative as a last second *oh shit* dodge, also works on ambushes and environmental hazards)
Durability: +5 Unc, +6 Death per level
Karma: Spend an action dice on any Charisma based test when the adept is attempting to deceive a target.
Discipline Talents:
Thread Weaving (Thief Weaving, everyone gets this to bind to magical items)
Awareness (includes search for traps chance as a Theif special ability)
Lock Picking
Picking Pockets
Stealthy Stride
Talent Options (choose 1 per level): [Initiate pool] Avoid Blow, Climbing, First Impression, Great Leap, Melee Weapons, Missile Weapons, Sprint, Surprise Strike, Taunt, Throwing Weapons

(Thieves get the Disarm Traps talent at second circle, but can roll raw Dex+HalfMagic [1/2 Circle] until then. Also, talents are all magic - allows karma action dice, but then you choose a few skills. So if you don't take a weapon style as a talent, you probably have it as a skill.)

Also, I do think that Thief skills are supposed to be extraordinary/fallback/emergency options. Everyone can sneak (you use the listen/surprise on x in 6 rules), but the thief has a chance of moving silently (bypassing the listen/surprise rolls). OR something like that, I found the original material doesn't present this part well (so various people have their interpretations).

Quote from: Larsdangly;832996I'm a fan of Castles and Crusades; I wonder if the 'White Box' version of that game would be a simple but 'tidied up' rules set for OSR games? I own the hard backs, but they have a scope and complexity more like 1E.

I don't really own White Box but I immediately thought of C&C when I read your OP, as it seems to tick all the boxes.

What's C&C not doing for you? Is it the 1e-like level of complexity (I actually feel it's much less complex) or is there something else?

Maybe Jason Vey's Spellcraft & Swordplay is what you're looking for. It hews closer to B/X than 1e and uses a unified mechanic -- 2d6 roll-high, patterned after Chainmail combat.

C&C is my jam; I am just sort of tired of having a stack of hard backs at the table whenever I game. That said, my post does sort of read like a wistful plea for a game I already own...

Delving Deeper is intended to be a close clone of OD&D pre-Greyhawk  It uses standard attack rolls and saves, but takes some scattered references in the LBBs and distills them into a universal method for skill rolls: everything succeeds on a 1 or 2 and 6, unless you think it should be harder (halve the odds to 1 in 6) or easier (double to 4 in 6). It then adds a Thief class that uses the 4 in 6 odds for all thief skills, which is better than 50-50.

What it doesn't do is use high ability modifiers. It uses the old max modifier of +/-1. To fix this for your needs, either substitute a later ability score table, or double the odds of success on skill rolls (4 in 6) for those with high relevant ability scores, halve them (1 in 6) for low scores.

Quote from: Telarus;833087Also, I do think that Thief skills are supposed to be extraordinary/fallback/emergency options. Everyone can sneak (you use the listen/surprise on x in 6 rules), but the thief has a chance of moving silently (bypassing the listen/surprise rolls). OR something like that, I found the original material doesn't present this part well (so various people have their interpretations).

While I don't have the original versions handy to check their presentations, ACKS lays it out in this way pretty clearly:  First check for surprise.  Then, if the monster isn't surprised, but it is distracted, check to see if it hears you.

Quote from: ACKS, p.99Under normal circumstances a passive monster can be snuck up on 33% of the time (2 in 6), while a distracted monster can be snuck up on 90% of the time (because it has a 15% chance of hearing something and a 66% chance of detecting the characters if it hears something).

Thief skills are only checked as a last resort if that initial 33% or 90% chance goes against you.

Quote from: nDervish;833140Thief skills are only checked as a last resort if that initial 33% or 90% chance goes against you.

I've read this interpretation but never thought it sounded like a very good 'read': Two separate rolls that use different mechanics and are described in different parts of the rules and don't actually refer to each other. I love my original D&D books, but this is the sort of hot mess that makes me prefer playing a more clearly written re-working at the table.

I like how Lamentations of the Flame Princess handles thief skills, and I folded that pretty seamlessly into ACKs.

Quote from: Larsdangly;832992- Your stats significantly impact your abilities.

How significantly do you want?. I like the LofFP / ACKs combintation as attribute bonuses, when compared to level, are significant at 1st level, minor at 3-4th, and not important at 9th.

Anything along the lines of B/X, or greater, impact of stats is good for me. I think characters feel most varied and interesting when every point on the attribute scale has some practical consequence.

Acks doesn't portray Move Silently and Hide in Shadows as fallback skills for when regular sneaking fails; instead a thief can use them straightaway to bypass the regular sneak rules.

*A successful Hide in Shadows (in dim conditions or with concealment) means even a monster watching an area can't see you (instead it counts as distracted, which means it only gets a Hear Noise roll).

*If you successfully make your Move Silently, you make no sound and they don't get to attempt the Hear Noise roll.

IIRC the sneaking section on pages 97-99 was added to the book as a result of a thread on Autarch's forums which brought up the same issue Larsdangly mentioned ( the various sneak mechanics being scattered throughout the book and failing to refer to one another).