Traits
Gear, spells, and creatures can have Traits — special properties that give them unique capabilities or limitations. Think of them as Roles or Maneuvers for non-player stuff, mechanical shortcuts that keep your game flowing without drowning you in lengthy explanations.
Conceits are unrated Traits — narrative truths that can't be measured but are absolutely true within the game world — they won't have numbers attached, same as for player characters. A demon might be Immune To Fire (unrated) rather than Resistant +3 (rated).
Compatible Traits stack normally. Resistant +2 and Protected +1 both apply to the same defensive situation (if at different points) while multiple Immune traits simply expand the range of things that cannot affect the target.
Many creatures and items will get a "Role" that is just whatever they are — "Bear", for example, or "Sylph" for a type of air elemental. They can then get Maneuvers relevant to that. Special items might get dedicated Maneuver-like rated bonuses in specific situations, such as Sharp for a supernally dangerous edge, or Flaming that provides light and ignites fuel in addition to its combat bonus.
This will cover a lot, but some things don't really fit well in that framework, and will use Traits to round out the edges. In a lot of cases, Traits are just a quick way to establish a shorthand for things that happen pretty often so the GM can create quick and concise descriptions that communicate the relevant basics on a sticky note or index card. If he makes a quick writeup for a ghost that is Stationary it means it's haunting a spot and won't chase the characters outside that area.
Note that a lot of "Traits" don't require actual writeups; they are just descriptive labels. Stationary is pretty obvious, and you should absolutely use it if it's relevant and appropriate, but there's nothing special about it. We're not even going to include it in the list here. It just means the thing is…well, stationary. You get the idea.
Some ideas are worth repeatable labels, though. When the GM scribbles "Inexorable" on a sticky note, players immediately know they are in trouble.
Behavioral Traits
Some creatures or objects act in predictable patterns that affect how players can interact with them.
Reactive — Only acts when triggered. Obviously this applies to a classic trap or magical ward that lies dormant until someone steps on the wrong stone, but it can also be a ghost that just won't notice you at all until you do that one thing… A herd of megafauna that have never seen humans may not fear you enough to react, but when you hurt one enough for it to call out, the rest may ALL respond.
Ablative — Degrades with use rather than having discrete charges. A magic wand might hold 10 points of energy to be spent in any increment, or a poison might lose potency with each attack roll regardless of whether it's resisted. Ablative things usually go away when all the battery of points is spent up.
Combat Traits
These modify how attacks and defenses work in ways that can dramatically alter tactical situations.
Inexorable — Does not allow Resistance rolls! This is extremely dangerous and should be commensurately rare and moderated. It should usually have a thematic domain in which it applies, which can be countered some other way; a spirit using a psychic wail might be Inexorable to the average Warrior, but a Conjuror might be able to establish a protective Ward.
Insidious — Cannot be opposed, only resisted. The attack bypasses active defense entirely. You can't use a sword to fight a poison already in your system, though a Healer might be able to use an antidote.
Subtle — effect is not obvious to anyone unable to perceive the Borderlands or the Spirit Realm.
Contagious — Spawns a copy of itself on any victim of a successful attack. Yes, this is as terrifying as it sounds. While this obviously applies to diseases, it could also be used for fire, especially if all the characters have had oil spilled on them…
Constrained — Limited to specific die types when making rolls. This is often used to indicate a lack of finesse. A forest ogre might be terrifyingly strong, but never roll anything but a d12.
Area Effect Traits
Area Effect: Targetable — Caster can use splitting to divide up the EL among different targets. (This is the default.)
Area Effect: Blanket — One roll applies equally to everyone and everything in the affected area. No splitting allowed.
Area Effect: Selective — Affects only targets meeting specific criteria: those wearing metal, supernatural beings, whatever the effect specifies. The method of selection should be specified in the spell — "only enemies" isn't something a fire effect could determine.
Note: Geometric shapes like cones or bursts are handled through narrative description. The mechanical distinction here is about targeting control, not drawing diagrams.
Defensive and Vulnerability Traits
Some things are tougher than expected — others have glaring weaknesses.
Immune — Completely unaffected by the specified attack type. Always provide alternative approaches — invulnerable enemies are boring enemies.
Vulnerable — Affected by things that wouldn't normally matter: cold iron against fae, salt circles against spirits, sunlight against vampires. How it applies is usually left to the description.
Hardened — Rating subtracts directly from incoming effect of the specified type before resistance. Different effect types are separate Traits. Broad types are possible, but be careful that they tell the right story.
Susceptible — Rating provides EL for environmental exposure to the specified type, or adds to active attacks using that type. The GM determines appropriate Traits (Insidious, Inexorable, etc.) based on circumstances.
Protected — Rating adds to Resisted effect after a successful Resistance roll.
Worsened — Rating always adds directly to incoming successful effect of the specified type.
Resistant — Rating adds to EL of resistance rolls against the specified effect type.
Sensitive — Rating adds to the EL of effects of the relevant type targeting this entity.
Spell-Specific Traits
Magic often behaves in ways that need mechanical precision.
Difficult — Requires a Difficulty Level roll to cast successfully. If casting succeeds, the DL usually becomes points of Inexorable effect that bypass normal Resistance. If a spell has DL0 it can be cast without a roll for "nominal" use, but Difficult spells or any actual effect always requires a roll to resist. Inexorable points are taken from the first points of rolled effect, and resistance is applied to any that remain; if fewer points are rolled, those points are all unresistable, but the rest of the Inexorable potential is lost.
Immutable — the spell has all Traits set when bound, and cannot be cast any other way.
Vancian — The spell erases itself from the caster's memory when used, regardless of success or failure. Old school and unforgiving. Some settings automatically apply this to ALL spells; the group may decide for themselves whether or not it still counts as DL reduction. Commonly used with Immutable, but not required (unless, again, ALL spells are both.)
Persistent — Trivial Effect continues beyond the initial casting without requiring concentration. For example — Light cast only for simple reading or navigation, rather than as an attack. Persistent spells need no special effort to maintain, and can stay active while casting other spells. They cannot hold an effect against someone else's roll, but might hold the spell active so that the caster can use it for new rolls.
Guidable — Caster can continue directing the effect after casting as long as they maintain line of sight.
Status — NOT accumulating. When cast again, replace the previous value rather than stacking.
Creating New Traits
Players and GMs should create new Traits when needed, but resist the urge to make everything into a Trait. Many effects that might seem like they need special mechanics are better handled through simple description.
A creature that can't move is just described as Stationary. You can treat it as a Trait without bothering to formalize it. Flying, burrowing, blindness, alternate senses — all of these work perfectly fine as narrative/descriptive elements without needing formal mechanical shortcuts.