Converting from 1E to BECMI or B/X

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Converting from 1E to BECMI or B/X

Postby Big Ulf » Tue Aug 08, 2017 10:30 pm

Hi all, I'm committed to sticking with RC/BECMI with a few of the better ideas in B/X thrown in.

Want to play some AD&D 1E modules and I figure I could wing it, but do any of you have a conversion guide that goes *from* 1E *to* BECMI?
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Re: Converting from 1E to BECMI or B/X

Postby Havard » Wed Aug 09, 2017 8:33 am

Hi there!

Converting from 1E (or 2E) to Classic D&D is really easy. I thin most people just wing it rather than using a particular conversion guide, but here are some thoughts.

When converting demihuman NPCs from AD&D to Classic you have to ask yourself: is the NPC's race or class the most important feature of this character? In most cases, elven fighters, elven mages, elven clerics etc will simply become elves in Classic. In some cases you might want to drop the race and simply keep the class instead and turn them into humans.

Half-Elves & Half-Orcs:
Use either human class or race (elf), but simply note the character's unusual heritage. See Darokin Gazetteer for more on these races.

You could simply drop the second part of the NPC's alignment, but I often find that the following can be just as appropriate:

Also note the odd things in BECMI such as Fey creatures being Chaotic, but noted as still being Good.

In AD&D, Unarmored characters have AC10. In Classic D&D, unarmored is AC9. Otherwise, keep same AC.

For monster Hit Dice, keep the same. However, note that some monsters in AD&D use other die types than D8 while this is extremely rare in BECMI. For NPCs, you will need to reroll Hit Points since characters use different die types than their BECMI counterparts.


Morale goes from 2-20 in AD&D, but from 2-12 in BECMI.

Ignore AD&D THAC0 and consult hit bonus chart from BECMI.


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Re: Converting from 1E to BECMI or B/X

Postby agathokles » Wed Aug 09, 2017 2:27 pm

Havard covered pretty much everything, but I'll add the following notes.

For NPC HPs, you can just reduce them by 1 per level for all NPCs of level 9 or less, except Wizards who are left unchanged. Statistically, it's almost the same as rerolling.

If you are using the rules material from the Gazetteers, Dragon Magazine, etc. (and not just the RC/BECMI books), then you have options for Dwarf Clerics, Elf Warriors, Elf Clerics, Elf Druids, Half-Elves, and demihumans with Thief skills. Half-Orcs can also become Orcs and use the Orc PC rules from Gaz 10, although in BECMI they are usually just humans with low charisma.

1e Assassins can become Thugs/Headsmen (the NPC type from the Master Set).

Regarding the alignment, I favor just dropping the Good/Evil part.

For monsters, you can usually just substitute the equivalent BECMI creature or even use them unchanged -- monster stat blocks are pretty compatible between the two games.

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Re: Converting from 1E to BECMI or B/X

Postby ripvanwormer » Wed Aug 09, 2017 4:53 pm

Havard wrote:Also note the odd things in BECMI such as Fey creatures being Chaotic, but noted as still being Good.

This is also true of djinn (noted in the Companion Rules as "basically good-hearted, though their behavior is very Chaotic"). Horde creatures and hydraxes are noted as being Lawful, but evil in BECMI.

Archons have "good intentions," but lawful neutral might be an accurate description of their behavior. I'd argue this is true of the protectors from the original B3 Palace of the Silver Princess, too.

I think there's some correlation between the BECMI "Lawful" alignment and what AD&D would call "good," but it's not an absolute one, and some creatures labeled Lawful translate as lawful neutral and lawful evil.
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Re: Converting from 1E to BECMI or B/X

Postby Big Ulf » Wed Aug 09, 2017 5:38 pm

Thanks gang, all helpful.

My main "concern" (if I can even call it that) is the level of opposition in modules of each edition.

1E was the game I played the longest, although I started with the B/X red box.
I read somewhere that the 1E modules had easier opposition for PCs than BECMI, at least in the early levels.
I've been playing BECMI again for about 3 years and loving it for the most part. But wanted to take my nephews through U1-3, and compared it many other basic modules U1 looks like a cakewalk (I played it way back in the day but memory of it has faded).

Is that analysis true, that if you want to run a typical 1E low level module in BECMI that you have to amp up the difficulty?

Thanks again
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Re: Converting from 1E to BECMI or B/X

Postby Cthulhudrew » Wed Aug 09, 2017 7:20 pm

Just to add my two cents, I mostly echo what Havard and Giampaolo already noted, but note that you might want to just decide from the outset if you want to go with a level to level conversion, or an XP to XP conversion. If you are doing a strict level to level conversion, you will have some differences in the XP and spellcasting between editions, chiefly.

Not too many of the AD&D modules went into very high levels that I can recall, and the XP differences don't really start to be noticeable until around 9th or so, but it is something to bear in mind.

As for the differences in difficulty, I'd say- at least to the best of my recollection- that they are roughly the same, but that you are always going to get variation between modules even within the same system. B8: Journey to the Rock, to me, was a fairly low difficulty module, as compared to B6: Rahasia, which was really tough on my players when I ran them through it. I think the same is going to be true of most of the AD&D modules (which admittedly I have less experience with running and playing in). I thought the A-series Slavelords modules were pretty tough, but not all other modules were the same. U1: Sinister Secret of Saltmarsh that you mention I seem to recall was more of an investigative module as opposed to hack and slash and heavy on roleplay, which might account for the lower difficulty.
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Re: Converting from 1E to BECMI or B/X

Postby Big Ulf » Fri Aug 11, 2017 2:58 am

Good point on focus of the module.

Thanks again all, love this forum.
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