1e Tomb of Horrors Conversion

[Kuroshima]

Originally Posted by Nymdok

The new one is set to a slightly lower 'Level' (9 as oppsoed to 10-14). There also appears to be more Saves versus the 'instant death' that is often found in the 1e adventure.

If all you have is the revised edition, and you understand the mechanics of that version, its a simple matter to convert using the same techniques Ive used. Its really just a matter of mapping the Damage from D&D to the Damage in GURPS. The same is true for the 'saving throws'.

Note that I didnt come up with those percentages casually. I figured what the expectation value would be for chars of a certain level and what the damage expectation would be for a given trap. Using that percentage I mapped it to 2xHP under the assumption that at -1 HP most people are largely out of the fight.

Similarly, I took the saving thorws for one of each class (F, T, MU, C) and averaged those together. Then I mapped that to a 3d6 probability and I allow the GM to decide what that success roll should be. For example, should a spring trap be a Roll vs Dodge or Per to avoid? I map the difficulty at 60% success, which is an 11 or less, and let the GM decide which is more suitable, and apply the modifiers from there.

For the record, if someone was familiar enough with the mechanics used in the revised version, Id LOVE to see a conversion done with that system and compare them. 1e books are all Ive got though :)

Nymdok

I've played more 3rd ed than 2nd ed (and 1st ed and OD&D were before my time), so I might give it a try. The thing to consider, for a D&D 3rd ed game, is that you can gauge it for the typical 4 man party, but a bunch of heavily optimized munchkins that use whatever came in the latest book will trounce whatever you've put there.

Saves:

Let's see, at level 9, the favored saves get a +6, while the non-favored saves get a +3. You also get to add an attribute (usually between +0 and +6 at this level) and you probably have an item that gives you a bonus +1 to saves. If someone has multiclassed, or taken prestige classes, then he will have even higher saves (as per RAW). This means that the expected saves will range from +4 (Fighter, Will) to 13 (Rogue, Reflexes), that we can average at +9.

Save DCs:

A quick check shows that most saves are DC 22-23, meaning that they will be effective 45-50% of the time against a delver's maxed save, and effective 90% of the time against a delver's ignored save. In order to replicate this, I recommend that you pick the dodge, and reduce it to 9-10 via penalties, for those traps that can be dodged, and take the best will and HT, and do the same.

Skills:

A delver gets an attribute bonus (+0 to +6), plus his skill ranks (min 0, max of level+3 if it's a class skill, (Level+3)/2 if it's not) plus about a +1 gear bonus, plus maybe a +1 magical or luck bonus. Thus an optimized rogue will have 12 (Skill ranks)+6 (Dex)+2 (Gear+magic) for a total of +20. This makes most traps extremely easy to disable, at the listed DCs.

Skill DCs: