An Example of Monster Conversion: The Sovereign Orb...

Good Morning, All:

Here's an example of my first steps as working up a conversion process for bringing D20 System creatures into the MyD20 Lite system. This is likely not the final process, as there is still room for refinement. However, it's what I've come up with after looking over several similar methods out there for converting D20 System creatures into retro-clone and original D&D rules sets.

From the Product Identity declaration in the Legal section of the D20 System Reference Document, Revised, you can see that the following monsters are declared Product Identity and are thus considered closed content: beholder, gauth, carrion crawler, tanar’ri, baatezu, displacer beast, githyanki, githzerai, mind flayer, illithid, umber hulk, yuan-ti. Legally, no OGL-based retro-clone should have any of these monsters present in their books, and when you check them out, you can see that none of them do.

However, there is hope for Open Content monsters that are reminescent of these "forbidden" creatures. The Iconic Bestiary: Classics of Fantasy, by Ari Marmell of Lion's Den Press, provides 3E statistics for seven new monsters, fully ready for use. Each one of these creatures correlates to one of the iconic monsters not included in the SRD. They are not the same creatures in disguise, but rather occupy the same niche, and possess comparable though not identical abilities. Given that these stats are Open Content, I can easily include them, or creatures inspired by them, in MyD20 Lite without a problem.

For example, let's look at the creature known as the beholder, the first on the list of Product Identity from the SRD's declarations. While I cannot release the beholder as part of my system's bestiary, I can take a page from The Iconic Bestiary. Ari Marmell wrote up a creature called the Evil Eye to replace the beholder. Given that I don't like the name "Evil Eye", since alignment is not a required part of MyD20 Lite, I have decided to call this creature a "Sovereign Orb".

In order to create the Sovereign Orb, we can start by converting the Evil Eye OGL stats from the D20 System into MyD20 Lite. The basic process for doing so is outlined below.

Name
The new creature's name is, obviously, Sovereign Orb.

Size
In order to convert the size of the creature into MyD20 Lite stats, I simply use the D20 System version, since the creature is not smaller than Tiny nor larger than Gargantuan. The Sovereign Orb is thus a Large creature.

Type (Subtype)
Since the Evil Eye is an Aberration, I will use the MyD20 Lite type of Monster. There are no subtypes listed, so I don't feel the need to select a subtype for this creature.

Hit Dice
Many of the basic values for a creature in MyD20 Lite are determined by the creature's Hit Dice. To properly convert a creature's HD from the D20 System to MyD20 Lite, start by taking the creature's base hit dice from the stat block. The Evil Eye has 11 hit dice, so that becomes our starting value. We then adjust the number of hit dice by taking the additional hit points (such as the Evil Eye's additional 33 hitpoints), dividing that number by 4.5 (to get 7.333), rounding the result down (which gives us 7), and adding that to the base hit dice (11 + 7 = 18). If the new total is more than double the base hit dice, limit yourself to double the base hit dice.

In this case, the Sovereign Orb will have 18 hit dice. That means that the average hit points for the Sovereign Orb would be 81.

Move
Under the D20 System, the Evil Eye has a base movement of 5 ft. and a fly movement of 30 ft. In MyD20 Lite, this translates to a movement rate of 1 square and a fly rate of 6 squares for the Sovereign Orb.

Armor Class
Looking at the Evil Eye's AC, after adding in size, Dexterity, natural armor, and deflection modifiers, we see that it has an armor class of 25. When I look at the average AC for an 18 HD monster in MyD20 Lite, I see that it should have a value of 27. Since the AC of the Evil Eye is within five points of the average value by Hit Dice, we can set the armor class of the Sovereign Orb at 25.

Attacks
Under the D20 System, the Evil Eye has two lash attacks, at +8 melee for 1d6–1 damage. Converting to MyD20 Lite, we need to first calculate the Sovereign Orb's basic combat values. Starting with 18 HD, we see that the Sovereign Orb starts with a +18 to attack and +9 on damage. When we modify these values for size, we see that the damage adjusts upward to +11, and the base damage for large creatures is 1d8. Monsters gain a +1 bonus on attacks, bringing the creature's attack value up to +19. I'd consider the lash to be somewhat equivalent to a wing buffet, as it is not as strong an attack form as a slam would be. This drops the damage for the lash attack down to 1d6. Taking all of this into account, the Sovereign Orb has the following attacks: two lashes +19 melee (1d6+11). This is a rather strong improvement over the Evil Eye's attacks, but for an 18 HD creature, this makes a certain kind of sense.

(As an aside, if I had decided to stick with the original 11 HD and not increase them for bonus hit points, the end result would have been: two lashes +12 melee (1d6+7), which is a little closer to the original. If that's the course you as a Referee would prefer to take, that would be okay, and in fact could be used to create a good Lesser Sovereign Orb stat block.)

Saving Throws
In MyD20 Lite, a creature's saving throws are based primarily on hit dice and monster type. In this case, the Sovereign Orb would have the following: Fort +16, Ref +16, Will +16. So far, the Sovereign Orb is looking a lot stronger in terms of game mechanics than the beholder that inspired it.

Special Attacks
Now we get down to the meat of the conversion: converting special attacks and qualities from the D20 System to MyD20 Lite. Looking over the Evil Eye's special attacks, I can easily see that it has gaze attacks as the only special attack listed. These gaze attacks can be noted in the MyD20 Lite stat block for the Sovereign Orb as: gaze attacks (choice of charm monster, confusion, inflict critical wounds, flame strike, hold monster, flesh to stone or sleep, Fort or Will DC 23 negates). You could even follow that up with notes that indicate the Sovereign Orb can only select one gaze attack per round as a Swift Action, the gaze attack lasts for only one round and once the Orb uses a given gaze attack, it can't be used for another 1d4 rounds.

Special Qualities
In terms of special qualities, the Sovereign Orb should have the following common special qualities: darkvision, damage reduction (half damage), energy reduction (half damage from acid, cold, electricity, fire and sonic) and telepathy. In addition, the All-Around Vision and Mystic Sight special qualities could also be added, along with descriptions for these uncommon abilities.

Challenge Rating and XP Value
A creature's Challenge Rating should be determined after the creature has been converted. In this case, we can determine that, according to MyD20 Lite, the Sovereign Orb now has a CR of 12. From that, we can determine that the XP Value for overcoming a Sovereign Orb is 14,400 XP.

For the curious, here's how I determined the Challenge Rating. The Base HD for the Sovereign Orb is 18. Using the CR Hit Dice Modifications Table, I determined the following CR HD Mods: Armor Class +6.25, Damage Reduction +1, Energy Reduction vs. five energy types +1.25, Gaze Attack +3 (based on the highest level spell that could be active at one time), All-Around Sight (moderate ability usable only some of the time) +0.25, Mystic Sight (moderate ability usable only some of the time) +0.25, Flight +1.25, Attacks (two 1d6 attacks) +1.5, Large Size +0.5, Magic Resistance +4, Very Limited Movement (Major Vulnerability) -1. These total +18.25. Since that is more than the Base HD, any excess is halved. The adjusted CR HD Mods is now +18.125, for a hit dice total of effectively 36.125. Consulting the Challenge Ratings by Total Hit Dice Table, a range of 36-38 hit dice equates to a Challenge Rating of 12.

Magic Resistance
Since the Evil Eye has spell resistance under the D20 System, the Sovereign Orb has magic resistance in MyD20 Lite. Typically, this is determined by adding the Challenge Rating of the creature to a base of 10. Therefore, this has to be calculated after the Challenge Rating, but knowing about it ahead of time helps in the calculation of the creature's CR. Thus, the Sovereign Orb has a Magic Resistance of 22.

The Final Product
Wow, that's a lot for a conversion, but the good thing is that for most of the basic monsters, this work will be done for you in either the MyD20 Lite Referee's Guide or MyD20 Lite Bestiary. Here's the final entry for the Sovereign Orb, including some descriptive text.

Sovereign Orb
The Sovereign Orb appears as an enormous floating eye, apparently ripped raw from the skull of some giant beast, with lengths of optic nerve that writhe and thrash behind it like tails, fading away after several feet into thin wisps of white mist. These "tails" are fully prehensile, allowing the Sovereign Orb to manipulate objects as well as human hands. Some are perfectly white, some yellowed, and some bloodshot. An Sovereign Orb’s iris can be of any color, from standard blues, greens and browns, to inhuman violets, golds and reds.

Sovereign Orbs have no concern for any living being other than themselves (and sometimes other Sovereign Orbs). They are capable of fighting with their optic nerve "tails," but prefer to remain at a distance and make use of their gaze attacks. Unless an Sovereign Orb believes itself overmatched, or believes it can bargain with or intimidate potential foes, it attacks without provocation. This is partly due to their obsession with acquiring magic, but also because they enjoy the kill.

Sovereign Orb: Large Monster; CR 12; XP 14,400; HD 18 (81 hp); MV 1, fly 6; AC 25; AT two lashes +19 melee (1d6+11); SV Fort +16, Ref +16, Will +16; MR 22; SA gaze attacks (choice of charm monster, confusion, inflict critical wounds, flame strike, hold monster, flesh to stone or sleep, Fort or Will DC 23 negates); SQ all-around vision, darkvision, damage reduction (half damage from physical attacks), energy reduction (half damage from acid, cold, electricity, fire and sonic attacks), mystic sight, telepathy.
Special Abilities:

• All-Around Vision: The Sovereign Orb can see all around itself, and so cannot be flanked.
• Gaze Attacks: The Sovereign Orb may only use a specific gaze attack effect for one round, and then must wait for 1d4 rounds before using it again. The Sovereign Orb may change from one gaze attack effect to another as a Swift Action.
• Mystic Sight: The Sovereign Orb can see magical emanations naturally. It is constantly treated as though under the effects of detect magic. Furthermore, it is treated as though it had spend three full rounds examining anything it sees, for purposes of recognizing the strength of auras, the school of magic, and the like. Additionally, the Sovereign Orb is also treated as though under a constant see invisibility affect.

Enjoy,
Flynn