These are proficiencies that don’t fall into a skill, but rather training using tools or equipment, like alchemical, vehicular, mechanical, or artisan skills.
Alchemy/Chemistry (INT)
This skill covers the crafting and knowledge of alchemical substances. Recalling knowledge allows the knowledge of identifying potions or substances.
Crafting Alchemical Substances (trained)
To craft alchemical substances, the crafter must have both the recipe and the training. Those who are untrained can attempt to brew a potion but take a skill setback. Each tier of a recipe requires the minimum Alchemy training level.
Failing the crafting dcr for an alchemical substance leads to a useless mess. Critical failure means you create a random potion with negative effects. Succeeding critically means your potion is one tier higher than it is.
Computers (INT)
Computers skill is knowing how to use a computer, from simple navigations to hacking to programming. Accessing a computer does not require a DCR, nor does using one most of the time. If you are using a computer for a timely task, the DCR is usually average.
Hacking
Hacking rules come in two varieties: hacker vs cyber defense, and hacker vs person. Cyber defenses come with their own DCR for defenses and countermeasures, while an actual person the hacker makes an opposed check. If a player is being counter-hacked, he can use his countermeasures to give him a boost to his defenses.
Healing/Medicine (WIL)
From first aid to long-term care, Healing allows a character to help injured people. For first aid, the DCR is average to assess the damage or hard to apply first aid. Curing diseases or poison requires a DCR= poison’s DCR+1, and for long term care it’s a passive check with a DCR of 2 each day.
Those who are trained in healing/medicine can offer better healing to those who are injured, applying medicines and salves to the injured party. Those who are trained also can remove poisons and heal wounds right away, granting temporary HP during adventuring mode (equal to the check over success of first aid). If the character loses all the temporary HP before they are fully recovered, their injury begins to bleed (see bleeding rules).
You are not required to have a set of medicinal/healers tools with you, however you will incur a -4 penalty to medicine/healers checks.
Mechanics (DEX)
Mechanics covers many different fields, from weapons and tools to architecture and wondrous devices. Recalling knowledge on mechanics allows you to get an understanding of various constructs. In addition, you can do repairs to your weapons, armors, and tools (see crafting and materials for further details.
Craft an item
to craft an item, you must have both the proper training and the schematic to craft that item. If you fail, you create a weaker version of that item. If you succeed critally, you improve its hardness or ability by 1.
Perform (CUN)
Vital to bards, Perform is the skill of using a musical instrument. Certain bardic abilities allow the use of Perform instead of other skills, including recalling knowledge, various arcana and lore skills, and spellcasting.
You can use perform to earn money as well. Depending on location and your performance, you could earn a pretty good living. The general DCR of performing for a night is average. If you succeed critically, you earn double the normal amount. If you fail, you earn half, and if you critically fail you are booed off the stage and can’t perform for one week.
Piloting, Driving, Operating
These proficiencies are specific to settings, and are about handling various vehicles and equipments, which will be covered in the Vehicle section of ARS.
Alchemical, Artisan, Instrument, Mechanical, and other Tools
These are specific tools that do have proficiency to use them, sometimes proficiency in these tools can boost other skill checks if you have proficiency in these tools and the tools themselves.
NightSong; Tales by the Fire Side 