Skills & Proficiencies
All characters are good at certain things. These are things that the character is said to be proficient at. There are a number of skills which a character may have proficiency with, as well as weapons and other tools. In addition characters may have knowledge in various areas which could be useful.
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[TH="width: 93, bgcolor: #944794"]Skill
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[TH="width: 147, bgcolor: #944794"]Primary Ability
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[TD="width: 93, bgcolor: #cfe7f5"]Acrobatics
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[TD="width: 147, bgcolor: #cfe7f5"]DEX[/TD]
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[TD="width: 93, bgcolor: #cfe7f5"]Arcana
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[TD="width: 147, bgcolor: #cfe7f5"]INT[/TD]
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[TD="width: 93, bgcolor: #cfe7f5"]Athletics
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[TD="width: 147, bgcolor: #cfe7f5"]STR[/TD]
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[TD="width: 93, bgcolor: #cfe7f5"]Bluff
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[TD="width: 147, bgcolor: #cfe7f5"]CHA[/TD]
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[TD="width: 93, bgcolor: #cfe7f5"]Diplomacy
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[TD="width: 147, bgcolor: #cfe7f5"]CHA[/TD]
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[TD="width: 93, bgcolor: #cfe7f5"]Engineering
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[TD="width: 147, bgcolor: #cfe7f5"]INT[/TD]
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[TD="width: 93, bgcolor: #cfe7f5"]Heal
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[TD="width: 147, bgcolor: #cfe7f5"]WIS[/TD]
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[TD="width: 93, bgcolor: #cfe7f5"]History
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[TD="width: 147, bgcolor: #cfe7f5"]INT[/TD]
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[TD="width: 93, bgcolor: #cfe7f5"]Insight
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[TD="width: 147, bgcolor: #cfe7f5"]WIS[/TD]
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[TD="width: 93, bgcolor: #cfe7f5"]Intimidation
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[TD="width: 147, bgcolor: #cfe7f5"]CHA[/TD]
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[TD="width: 93, bgcolor: #cfe7f5"]Leadership
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[TD="width: 147, bgcolor: #cfe7f5"]CHA[/TD]
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[TD="width: 93, bgcolor: #cfe7f5"]Nature
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[TD="width: 147, bgcolor: #cfe7f5"]WIS[/TD]
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[TD="width: 93, bgcolor: #cfe7f5"]Perception
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[TD="width: 147, bgcolor: #cfe7f5"]WIS[/TD]
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[TD="width: 93, bgcolor: #cfe7f5"]Religion
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[TD="width: 147, bgcolor: #cfe7f5"]INT[/TD]
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[TD="width: 93, bgcolor: #cfe7f5"]Stealth
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[TD="width: 147, bgcolor: #cfe7f5"]DEX
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[TD="width: 93, bgcolor: #cfe7f5"]Streetwise
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[TD="width: 147, bgcolor: #cfe7f5"]CHA
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[TD="width: 93, bgcolor: #cfe7f5"]Survival
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[TD="width: 147, bgcolor: #cfe7f5"]CON[/TD]
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[TD="width: 93, bgcolor: #cfe7f5"]Thievery
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[TD="width: 147, bgcolor: #cfe7f5"]DEX[/TD]
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Skills
A skill represents an area of endeavor or proficiency. Many skills are 'knacks', for instance a character proficient in the Athletics skill is particularly good at athletic feats and will probably naturally prefer to use them to solve problems.
Others might best be seen as talents a character possesses and associated knowledge and expertise. Again, these are things a character might naturally prefer to use in problem solving.
Having a skill may also imply a certain amount of general knowledge which goes with it. For instance a character with proficiency in the Streetwise skill knows facts about towns and their back streets and is at home navigating them.
Proficiency
If a character is trained in a skill then the character has proficiency with this skill and gets the +5 proficiency bonus to all checks using this skill. Any character may attempt to use any skill, but some have natural aptitude, training, or experience which gives them an edge. Some powers may require proficiency with a given skill. The character must have proficiency in the relevant skill to attempt that check.
Proficiency is also an indication of the types of activities which a character is familiar with and will achieve good results with. When characters are outside of conflict situations they may use their skills and will generally be successful at the things they are good at. Thus a Wizard might research a new type of ritual he wishes to develop. His knowledge of Arcana is likely to allow him to succeed.
Skill Powers
Some skills also have basic powers associated with them. These are basic powers which any character may attempt to use. Naturally, being proficient with the skill will make these easier to use effectively.
Descriptions
All of the above skills are described here. The situations in which proficiency in this skill may typically be applied to checks are discussed, along with typical DVs associated with those checks and additional situations which may modify them. Powers associated with the skill are then described.
4e's skill system is pretty much fine. I did note that there were a couple of rather obvious things missing. Leadership and Engineering being the obvious additions. I got rid of 'dungeoneering' as being rather D&D-specific. In any case we often used it to stand in for an Engineering skill, so that seemed like a decent tweak.
In any case, as I've propounded in discussions of 4e skills, these are meant to be something a bit more like Fate Accelerated's approaches, but in a more concrete form. Between a character's ability scores and skill check bonuses it becomes fairly easy to determine what their characteristic approaches to problem-solving are.
Note however that in the context of HoML all sorts of checks, which are going to be mostly skill checks in all likelihood, take on a slightly different aspect than in 4e. All 'scenes' are either challenges in-and-of-themselves, or they form some element of an ongoing challenge. There is no such thing as a simple check unassociated with any challenge, unless the situation is an action sequence (combat mostly) where the detailed action rules govern the progress of the scene.
All checks are part of the success/failure tally system of the general challenge mechanics. While there is a success and failure associated with each individual check, the really significant strategic success/fail determinations will be for overall challenges (IE 3 fails and you take the 'failed' branch of the story). This means that skill checks themselves are more involved in steering the immediate narrative within a scene. For this reason they partake of the general 4 levels of result check mechanism, critical failure, failure, success, and complete success. This gives the GM some pretty strong support in terms of deciding what happens and how it drives the story forward.
Another thing to note with HoML is the role of Practices. Practices are not fundamentally a set of almost skill-like things. Instead they server two purposes within this structure. First they are little mini-narratives which players can invoke in order to take control of which skills are going to be engaged. For example: the wizard comes to a locked door. Not desiring to engage in a bout of lock-picking for which he's ill-suited, he chooses to alter the narrative into a story of how he uses his Undo ritual to make an arcana check to open the lock. This illustrates the 'substitute a different skill' effect of practices. The other aspect is their 'bypass a check' function, which can be engaged by paying any 'boost' price. In that case the wizard simply expends a Vitality Point (some life force) and the door AUTOMATICALLY opens, presumably leading to a success being tallied in the current ongoing challenge.
The boost aspect of practices illustrates the 'up the ante' mechanism of HoML in action. When it REALLY matters to a character to pass a skill check, then she will! It will just come with a price. Players will have to pick and choose what 'really matters' in a given situation, since they won't have limitless VPs to burn. A player could also leverage a character trait and Inspiration to invoke a "the door is simply not locked" scenario (this might work for a character with the trait 'lucky' for example), or some other equivalent narrative that would relate to some other trait. Other character attributes may be called out as well, such as an unusually high ability score, a background element, or a boon.
Inspiration and boost overlap to a certain extent, but they serve slightly different purposes. One aligns play to the character's traits, the other to its skills or 'knacks'. To the extent that these are all part of a holistic character design concept they will all contribute to the narrative realization of that concept in play.