DnDGen.CreatureGen 2.0.0

CreatureGen

Generates a random, fleshed-out creature for Dungeons and Dragons 3.5

Installing CreatureGen

The project is on NuGet. It targets .NET 10.

dotnet add package DnDGen.CreatureGen

Getting the Generators

You can obtain generators from the IoC namespace within the domain project. Because the generators are very complex and are decorated in various ways, there is not a (recommended) way to build these generators manually. Please use the Module Loader in the IoC namespace. Note: This will also load dependencies of CreatureGen, including RollGen, Infrastructure, and TreasureGen.

var kernel = new StandardKernel();
var creatureGenModuleLoader = new CreatureGenModuleLoader();

creatureGenModuleLoader.LoadModules(kernel);

var creatureGenerator = kernel.Get<ICreatureGenerator>();
var creatureVerifier = kernel.Get<ICreatureVerifier>();

Your particular syntax for how the Ninject injection should work will depend on your project (class library, web site, etc.)

Use

Generating a specific creature

var ogre = creatureGenerator.Generate(false, CreatureConstants.Ogre);
var zombieOgre = creatureGenerator.Generate(false, CreatureConstants.Ogre, null, CreatureConstants.Templates.Zombie);
var humanCharacter = await creatureGenerator.GenerateAsync(true, CreatureConstants.Human);

The first argument, asCharacter, says whether the creature is generated as a character (a playable race that will take class levels) or as a monster. Only creatures that can be characters may be generated as characters. For example, a 1-Hit-Die humanoid such as a Human has its racial Hit Die replaced by class levels when generated as a character.

Chaining templates

Templates are passed as the last arguments, and are applied in the order given. Each template must be compatible with the creature as it is after the templates before it have been applied.

var halfDragonHalfFiend = creatureGenerator.Generate(
    false,
    CreatureConstants.Human,
    null,
    CreatureConstants.Templates.HalfDragon_Black,
    CreatureConstants.Templates.HalfFiend);

Ability scores

When no AbilityRandomizer is passed in, abilities are rolled with the default roll (1d2+9, or 10-11) with no other modifications.

var abilityRandomizer = new AbilityRandomizer(AbilityConstants.RandomizerRolls.BestOfFour);
abilityRandomizer.PriorityAbility = AbilityConstants.Intelligence;

var elfLich = creatureGenerator.Generate(true, CreatureConstants.Elf_High, abilityRandomizer, CreatureConstants.Templates.Lich);

//INFO: Set rolls are used as-is instead of rolling
var setRandomizer = new AbilityRandomizer();
setRandomizer.SetRolls[AbilityConstants.Strength] = 18;
setRandomizer.SetRolls[AbilityConstants.Charisma] = 8;

var strongDwarf = creatureGenerator.Generate(true, CreatureConstants.Dwarf_Hill, setRandomizer);

The available rolls are in AbilityConstants.RandomizerRolls:

Some templates require a minimum ability score: a Ghost needs Charisma 6, and a Half-Celestial or Half-Fiend needs Intelligence 4. When you generate one of these, any rolled score that would fall short is raised to meet the minimum. If the randomizer can never reach the minimum (for example, a set roll that is too low), the creature is not compatible and an InvalidCreatureException is thrown.

Random creatures

var (creatureName, templates) = creatureGenerator.GenerateRandomName(false);
var randomCreature = creatureGenerator.GenerateRandom(false);
var randomCharacter = await creatureGenerator.GenerateRandomAsync(true);

//INFO: A random creature with the given template(s)
var randomGhost = creatureGenerator.GenerateRandom(false, null, null, CreatureConstants.Templates.Ghost);

//INFO: Pass the None template to only get creatures without a template
var randomNonTemplated = creatureGenerator.GenerateRandom(false, null, null, CreatureConstants.Templates.None);

When no templates are passed in, the random creature may or may not have a template, weighted heavily in favor of creatures without a template.

Filters

Filters narrow down which random creatures are valid. They are checked against the creature after all of its templates are applied.

• A creature satisfies a filter if it matches any of the values in that filter's list.
• A creature must satisfy every filter that has values.
• Null and empty filters are ignored, so new Filters() allows anything.

var filters = new Filters
{
    Types = [CreatureConstants.Types.Humanoid],
    ChallengeRatings = [ChallengeRatingConstants.CR3, ChallengeRatingConstants.CR4],
    Alignments = [AlignmentConstants.NeutralEvil, AlignmentConstants.ChaoticEvil],
};

var randomNameWithFilters = creatureGenerator.GenerateRandomName(false, filters);
var randomWithFilters = creatureGenerator.GenerateRandom(false, null, filters);
var randomHalfFiend = await creatureGenerator.GenerateRandomAsync(false, abilityRandomizer, filters, CreatureConstants.Templates.HalfFiend);

Types matches both creature types and subtypes, such as CreatureConstants.Types.Subtypes.Reptilian. Creatures generated with a challenge rating filter are never advanced, so their challenge rating stays predictable.

Checking compatibility

If the creature, templates, ability randomizer, and filters can't produce a valid creature, the generator throws an InvalidCreatureException. To check ahead of time, use the ICreatureVerifier:

var canBeGhost = creatureVerifier.VerifyCompatibility(false, CreatureConstants.Ogre, null, null, CreatureConstants.Templates.Ghost);
var anyValidCreature = creatureVerifier.VerifyCompatibility(false, null, abilityRandomizer, filters);

When no templates are given, VerifyCompatibility returns true if any template (or no template) gives a valid creature. Include CreatureConstants.Templates.None to only check creatures without a template.

Upgrading from 1.x

Version 2.0.0 has breaking changes to the public API:

• Targets .NET 10. Version 1.x targeted .NET 8, which reaches end of support on November 10, 2026.
• Templates moved out of Filters. Pass templates as the trailing params string[] templates argument of GenerateRandomName, GenerateRandom, and GenerateRandomAsync instead of Filters.Templates.
• Filters are now lists. Filters.Type, Filters.ChallengeRating, and Filters.Alignment are replaced by Filters.Types, Filters.ChallengeRatings, and Filters.Alignments. A creature matches if it matches any value in a list.
• Filters.GetDescription(bool asCharacter) is now Filters.GetDescription().
• AbilityRandomizer.Roll is set through the constructor, for example new AbilityRandomizer(AbilityConstants.RandomizerRolls.Good). The parameterless constructor still uses the default roll.
• ICreatureVerifier.VerifyCompatibility now takes the ability randomizer and the templates: VerifyCompatibility(asCharacter, creature, abilityRandomizer, filters, templates).
• InvalidCreatureException constructors now take Filters, an AbilityRandomizer, and templates, and the message includes all of them.
• CreaturePrototype is now internal.
• New challenge ratings ChallengeRatingConstants.CR28, CR29, and CR30.