Converting old AC Over to New? [Archive] - Wizards Community

Converting old AC Over to New? [Archive] - Wizards Community

Post/Author/DateTime Post
FatesWarning
08-09-07, 11:39 AM Hello ALL,

I use to play alot of D&D back in the day, Basic/Expert and 2.0 So now looking at all of the new stuff, being away for for so long can get a bit overwhelming, but it sure has been a lot of fun.

Anyway, me and my friends would like to play some old mods. that we have, but ofcourse the AC is the old style 0 or even -3 or whatever.
If i encounter someone with a -3 AC, what would that be with the new style AC?

And do you have any other sugestions, on using older modules, with the new system 3.0 or even 3.5( which i know little about)?

Thank for your time!!!
Steely_Dan
08-09-07, 11:43 AM Old AC = new AC

10 = 10
9 = 11
8= 12

Etc…

0 = 20

-10 = 30
vaerdhdragonkin
08-09-07, 11:47 AM It would depend on what they have for armor. Generally speaking, a straight conversion won't work. I don't recall if an unarmored individual had a "base" AC in 2nd Ed rules. Anyone? Bueller?
Hsien
08-09-07, 11:51 AM You kind of have to look at what gives it that AC.
With changes to armor, it may not equal the simple formula.

Simple formula:
Old AC 10 = New AC 10 ... that still amuses me.
Basically you simply loom at the difference of the the Old Ac to Old AC 10; then you add that difference to 10 to get the new 3.5 AC

Therefore
Old AC -3 ( difference of 13 from Old AC 10 ) = New AC 23 : ( 13 + 10 )

Again thats a simplified method, that doesn't always work with changes to armor and dex restrictions in 3.5.

As far as using old modules; my group has done it but you really have to look at the monsters in there and what there 3.5 challenge rating is.

For example; Against the Gianys starts at lvls 8-10 for the Hill Giant Steady; I don't know what a Hill Giants CR is off hand, but the 3.5 conversion is probably closer to 10-14.
Steely_Dan
08-09-07, 11:57 AM If i encounter someone with a -3 AC, what would that be with the new style AC?

23.
Tempest Stormwind
08-09-07, 12:28 PM You might find this (http://www.wizards.com/dnd/files/conversionbook.zip) to be worthwhile. It showcases the major mechanical differences between AD&D2e and 3e.

From there, this (http://wizards.com/dnd/files/DnD35_Core_Books.zip) highlights the major changes from 3e to 3.5.

They are not perfect, but it'll give you a sense of what something would be in different editions. For instance, an NPC in a module might have an AC of 18 and DR 5/magic; in AD&D, this would probably be expressed as AC 2, +1 or better weapon to hit.
Khedron
08-09-07, 01:42 PM If you look around, you can find conversions for many old modules. They normally have the stats converted, as well as treasure.
RogerWilco
08-10-07, 04:34 AM The tricky thing about a conversion to 3/3.5 is that the old system is not linear like the new system, so 19 DEX is a lot better then 18 DEX, but 12 DEX is about the same as 8. Not even mentioning what a STR of 18/75 would mean.

AC conversions are on the other hand pretty simple, like the above already pointed out.

Good luck!
Kursk
08-10-07, 09:51 AM I don't recall if an unarmored individual had a "base" AC in 2nd Ed rules. Anyone? Bueller?

AC 10
Seldriss
08-10-07, 11:28 AM I can't believe nobody gave the answer for the conversion yet...

That's simple : Add -20 and ignore negatives

Old AC/New AC
10/10
9/11
8/12
7/13
6/14
5/15
4/16
3/17
2/18
1/19
0/20
-1/21
-2/22
-3/23
-4/24
-5/25
-6/26
-7/27
-8/28
-9/29
-10/30
...
Tempest Stormwind
08-10-07, 12:08 PM I can't believe nobody gave the answer for the conversion yet...

...

I did. By linking the document that shows *every* conversion factor between AD&D and 3e.

Including, but not limited to:
Exceptional Strength -> regular scale Strength
Proficiency score -> Skill modifier
Thac0 -> Attack bonus
Old AC -> New AC
Old saves -> New saves (both in terms of type and in terms of numbers)
Old XP when single-, dual- or multi-classed -> New XP (reasonably accurate)

...And so on and so forth.

Post/Author/DateTime	Post
FatesWarning 08-09-07, 11:39 AM	Hello ALL, I use to play alot of D&D back in the day, Basic/Expert and 2.0 So now looking at all of the new stuff, being away for for so long can get a bit overwhelming, but it sure has been a lot of fun. Anyway, me and my friends would like to play some old mods. that we have, but ofcourse the AC is the old style 0 or even -3 or whatever. If i encounter someone with a -3 AC, what would that be with the new style AC? And do you have any other sugestions, on using older modules, with the new system 3.0 or even 3.5( which i know little about)? Thank for your time!!!
Steely_Dan 08-09-07, 11:43 AM	Old AC = new AC 10 = 10 9 = 11 8= 12 Etc… 0 = 20 -10 = 30
vaerdhdragonkin 08-09-07, 11:47 AM	It would depend on what they have for armor. Generally speaking, a straight conversion won't work. I don't recall if an unarmored individual had a "base" AC in 2nd Ed rules. Anyone? Bueller?
Hsien 08-09-07, 11:51 AM	You kind of have to look at what gives it that AC. With changes to armor, it may not equal the simple formula. Simple formula: Old AC 10 = New AC 10 ... that still amuses me. Basically you simply loom at the difference of the the Old Ac to Old AC 10; then you add that difference to 10 to get the new 3.5 AC Therefore Old AC -3 ( difference of 13 from Old AC 10 ) = New AC 23 : ( 13 + 10 ) Again thats a simplified method, that doesn't always work with changes to armor and dex restrictions in 3.5. As far as using old modules; my group has done it but you really have to look at the monsters in there and what there 3.5 challenge rating is. For example; Against the Gianys starts at lvls 8-10 for the Hill Giant Steady; I don't know what a Hill Giants CR is off hand, but the 3.5 conversion is probably closer to 10-14.
Steely_Dan 08-09-07, 11:57 AM	If i encounter someone with a -3 AC, what would that be with the new style AC? 23.
Tempest Stormwind 08-09-07, 12:28 PM	You might find this (http://www.wizards.com/dnd/files/conversionbook.zip) to be worthwhile. It showcases the major mechanical differences between AD&D2e and 3e. From there, this (http://wizards.com/dnd/files/DnD35_Core_Books.zip) highlights the major changes from 3e to 3.5. They are not perfect, but it'll give you a sense of what something would be in different editions. For instance, an NPC in a module might have an AC of 18 and DR 5/magic; in AD&D, this would probably be expressed as AC 2, +1 or better weapon to hit.
Khedron 08-09-07, 01:42 PM	If you look around, you can find conversions for many old modules. They normally have the stats converted, as well as treasure.
RogerWilco 08-10-07, 04:34 AM	The tricky thing about a conversion to 3/3.5 is that the old system is not linear like the new system, so 19 DEX is a lot better then 18 DEX, but 12 DEX is about the same as 8. Not even mentioning what a STR of 18/75 would mean. AC conversions are on the other hand pretty simple, like the above already pointed out. Good luck!
Kursk 08-10-07, 09:51 AM	I don't recall if an unarmored individual had a "base" AC in 2nd Ed rules. Anyone? Bueller? AC 10
Seldriss 08-10-07, 11:28 AM	I can't believe nobody gave the answer for the conversion yet... That's simple : Add -20 and ignore negatives Old AC/New AC 10/10 9/11 8/12 7/13 6/14 5/15 4/16 3/17 2/18 1/19 0/20 -1/21 -2/22 -3/23 -4/24 -5/25 -6/26 -7/27 -8/28 -9/29 -10/30 ...
Tempest Stormwind 08-10-07, 12:08 PM	I can't believe nobody gave the answer for the conversion yet... ... I did. By linking the document that shows every conversion factor between AD&D and 3e. Including, but not limited to: Exceptional Strength -> regular scale Strength Proficiency score -> Skill modifier Thac0 -> Attack bonus Old AC -> New AC Old saves -> New saves (both in terms of type and in terms of numbers) Old XP when single-, dual- or multi-classed -> New XP (reasonably accurate) ...And so on and so forth.