A ROUGH GUIDE FOR CONVERTING AD&D 1ST AND 2ND EDITION TO HERO

Converting First (and Second) Edition Advanced Dungeons and Dragons characters and monsters to the HERO System 5th Edition is not the easiest task in the world, primarily due to AD&D's Level, Hit Dice (and Points), Armor Class, and Saving Throw system. However, it can be done, it just takes work. The conversions presented here are (admittedly) rough ones. I am attempting to capture the flavor the original creature, with most of the powers and abilities intact, but I'm not trying for a perfect translation.

The basic format for translation was taken from Second Edition Fantasy Hero. It works as follows (with some additions from me):

STR Based off of the creature's Size (see the HERO System Bestiary, pages 26-27). Note that HERO STR goes much high then 1st & 2nd Edition AD&D STR (which tops out at 25). For the most part, AD&D STR = HERO STR. However, large creatures should get their STR per their size. Thus, we avoid the problem of 20' tall Storm Giants having a "mere" 24 STR and being unable to lift their own body weight.
DEX 10 + Hit Dice. Note this means large creatures are also fast creatures. While that works well for demons, devils, and the like, it doesn't work so well for whales and dinosaurs (both of which would have DEX scores of 20-46 using this system). If all else fails, base the DEX off of creatures of similar size found in the HERO System Bestiary.
CON Based off of the CON of creatures of similar size found in the HERO System Bestiary.
BODY 8 + (HP/10). Also based off of the creature's Size (see the HERO System Bestiary, pages 26-27).
INT Listed Intelligence. This is often modified per creatures listed in the HERO System Bestiary.
EGO Usually equal to INT. May be modified per creatures listed in the HERO System Bestiary.
PRE Based off of the creature's Size (see the HERO System Bestiary, pages 26-27).
COM Based off of the COM of similar creatures found in the HERO System Bestiary.
PD Usually 2 x Figured.
ED Usually 2 x Figured.
SPD Round up from Figured.
REC Figured.
END Figured.
STUN Figured.
Movement Move/2. Note—this makes many creatures fairly slow, at least in HERO terms. Movement is often modified per the creature's Size.
Resistant DEF 8 - Armor Class (minimum of 0). This tends to lead to resistant DEFs in the 3-6 range. A negative Armor Class should simply add to the base 8. So an Armor Class of 0 = 8 DEF, an Armor Class of -1 = 9 DEF. Be aware that AD&D Armor Class also accounts for the creature's DEX. If a low Hit Dice creature has a high Armor Class, then consider increasing the base DEX. If a DEX is listed in the text, then use that value as given.
Damage Classes Max Damage/3. Be aware this can led to some high Damage Class attacks. For example, the remorhaz's red-hot back does 10-100 points of damage in AD&D. This would be (100/3 = 33) either 33 dice of Energy Blast, or 11d6 of Killing Damage. Way more than is needed for the typical game.
OCV 3 + HD. This can lead to extremely high OCVs, however.
DCV (10 + HD)/3.

While this usually leads to some workable stats there is obviously room for customization, common sense, and general editing. Most other creature powers can be created based on what the text has to say, what we know about AD&D (i.e. all monsters have Infravision), and what similar creatures are capable of in such books as the HERO System Bestiary or the HERO System Asian Bestiary Volumes I and II. Finally, don't forget the various Creature Templates found on pages 21 to 30 of the HERO System Bestiary. They can help fill in various powers and abilities a specific creature many have.

Defenses: Defenses in AD&D can be tricky. Many creatures are immune to certain attack forms. The best way to simulate this is to give the creature Physical or Energy Damage Reduction, Resistant, 3/4, and place a limitation of "Only Versus X" per page 78 of HERO System 5th Edition. Add in 20 DEF Armor, only versus the same sort of attack and you should be all set.

Distance: When converting breath weapons and spell effects, I went with a formula of 1" = 10 yards (AD&D's "outside" scale). Thus, all I had to do was divide any numbers in two to get HERO System game inches.

Time: Remember, in AD&D, 1 Turn is 10 Minutes, 1 (Melee) Round is 1 Minute, 1 Segment is 6 Seconds. Creatures who can cast a spell "Once Per Round" technically can cast said spell once per Minute, which makes said powers virtually useless in HERO's combat system. For the most part, I presume any spell-like ability to be castable once per Phase, while anything that takes 1 Turn to actually take 10 Minutes. This is best simulated as follows: One Recoverable Charge (takes 10 Minutes to recover; -1 1/4). If you wish, make the power recoverable every Turn, thus preserving the AD&D intent while making the power a bit more useful in HERO.

Magic Use: When converting specific spells, I checked the Player's Handbook and did my best to adapt from there. Creatures who have magical ability (i.e. Clerical, Druidical, Illusionist, or Magic User spell levels) simply get an allotment of points to spend on spells and the like. Some creatures, such as the kirin and it's 18th-level magic user ability, might be better served with a Variable Power Pool.

Magic Resistance: Probably the biggest problem in translating AD&D to HERO System is magic resistance. Simply put, magic resistance is the chance of a spell from an 11th-level character failing outright when used on the target creature. This chance goes down by 5% for each level above 11, and up by 5% for each level below 11. Thus, a creature with 50% Magic Resistance has a 50/50 chance of a spell cast on it by an 11th level character failing outright, before any saving throw is needed. For a 10th level character, the chance is 55%, for a 12th level character, 45% (and so on). How does one convert this to HERO System? There is no direct way, but there are ways to simulate this with HERO System game mechanics. For the record, I will not be using any form of magic resistance on my character sheets.

Desolidification: The basic idea behind magic resistance is that spells simply do not affect the target. They fail to work outright, leaving the creature totally unharmed. You can simulate this by using Desolidification as a defense. The attack being defended against is magic, specifically, magic spells and spell effects—thus, enchanted weapons still work normally, but a lightning blast from a magic wand would be affected. The base form of the power looks like this:

Magic Resistance: Desolidification, Inherent (+1/4), Reduced Endurance (0 END; +1/2), Persistent (+1/2), Personal Immunity (+1/2) (110 Active Points); Always On (-1/2), Only To Protect Against Magic (-1). Total cost: 44 points.

This represents 100% magic resistance. See the charts below for more on translating the different percentages of magic resistance into Activation Rolls. Technically, this power requires the creature to buy Affects Physical World on STR and all powers that affect physical objects, but you can give "GM's Permission" to ignore this aspect (especially since it is so central to AD&D's game world).

Dispel: Dispel simulates the spell failure aspect quite well, but has the major drawback of being very expensive. You need around 20d6 (60 Active Points) of Dispel to effect most HERO System spells (such as 8d6 Explosion fireballs and 4d6 RKA lightning bolts). I also recommend using the Set Effect Rule, automatically dispelling 60 Active Points of any magical attack. However, as I said, this is a very expensive power, as you need various Advantages in place to allow the magic resistance to affect incoming spells before the hit the target creature. Borrowing a rule from Suppress (see below), the Area Of Effect Advantage is used to create a "magic resistance field," while the Self Only Limitation is used to represent the idea the field only affects the creature itself, not people around it. The base form of the power looks like this:

Magic Resistance: Dispel Magic Spells 20d6 (set effect 60 Active Points dispelled), all Powers with a magic spell special effect simultaneously (+2), Area of Effect (One Hex; +1/2), Continuous (+1), Inherent (+1/4), Personal Immunity (+1/4), Reduced Endurance (0 END; +1/2), Persistent (+1/2) (360 Active Points); Always On (-1/2), No Range (-1/2), Self Only (-1/2). Total cost: 144 points.

As with the Desolidification power, you need to add an Activation Roll for differing levels of magic resistance. The major drawback to this power is that not even 20d6 of Dispel can affect some HERO System spells, while in AD&D magic resistance can defend a creature from any spell, no matter how powerful (provided the creature makes its magic resistance roll).

Suppress: Suppress works like Dispel, but has one major advantage—it always works. It can totally Suppress small powers and reduce the effect of large ones, and like AD&D's magic resistance, large (i.e. high-level) spells will still affect the creature. However, unlike AD&D, it is not an "all or nothing" power. In AD&D, magic resistance either eliminates the spell or it works perfectly, while Suppress modifies the power level of all incoming spells. As a final note, this power does use the concept of a "Suppression Field" as seen in the HERO System 5th Edition rulebook. The base form of the power looks like this:

Magic Resistance: Suppress Magic Spells 12d6 (set effect 36 Active Points suppressed), all Powers with a magic spell special effect simultaneously (+2), Area of Effect (One Hex, Accurate; +1/2), Inherent (+1/4), Personal Immunity (+1/4), Reduced Endurance (0 END; +1/2), Persistent (+1/2) (300 Active Points); Always On (-1/2), No Range (-1/2, Self Only (-1/2). Total cost: 120 points.

As with Desolidification and Dispel, you need to add an Activation Roll for differing levels of magic resistance. You may also want to increase the amount of dice to 20d6 in order to get the same range of effects as Dispel. This will, however, dramatically increase the cost of the power.

Percentage To Activation Roll Table:

3 - = .46% (round to 1%)
4 - = 1.85% (round to 2%)
5 - = 4.63% (round to 5%)
6 - = 9.26% (round to 10%)
7 - = 16.20% (round to 15%)
8 - = 25.93% (round to 25%)
9 - = 37.50% (round to 40%)
10 - = 50.00% (round to 50%)
11 - = 62.50% (round to 60%)
12 - = 74.07% (round to 75%)
13 - = 83.80% (round to 85%)
14 - = 90.74% (round to 90%)
15 - = 95.37% (round to 95%)
16 - = 98.15% (round to 100%)
17 - = 99.54% (round to 100%)
18- = 100%

The "round to" is for use in translating from AD&D to HERO System.

The Limitation table in 5th Edition only goes to 8-, an expanded Limitation table is as follows:

Roll Bonus
3- -3 1/2
4- -3
5- -2 3/4
6- -2 1/2
7- -2 1/4
8- -2
9- -1 1/2
10- -1 1/4
11- -1
12- -3/4
13- -3/4
14- -1/2
15- -1/4
16- -0
17- -0
18- -0

When converting from AD&D to HERO System you should round the creature's magic resistance roll to the nearest 5%, and only use Activation Rolls from 5- to 15-, as anything lower than 5% should be rounded to 5%, and anything higher than 95% is simply rounded to 100%.


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