Arcydea allows Downtime, which allows characters to extend or improve their skills and attributes, take on new feats, learn or develop new spells, and more. When working on a specific task, Downtime hours are tracked simply (began working on X on 4/30), and accumulated as the sheet is updated.

In addition, Downtime days may be awarded for adventures that take more real time than character time (two weeks to finish a plot that resolves in two days means 12 days of downtime) or more character time than real time (a plot that resolves in a week from a character's perspective that is played out in one evening adds 6 days of downtime.) These are effectively additional adventure rewards, and XP rewards may be adjusted accordingly.

Arcydea allows characters to expand and grow in ways not quite covered by DND 5e RAW, and modifies the systems provided in the PHB and DMG significantly. As such, the relevant options are provided below.

• Learning a Language. You automatically know the languages available via RAW; however, you can gradually learn additional languages with Downtime. Note that if you are in a country that constantly speaks a language you are trying to learn, all Downtime spent is doubled (as you are basically spending every waking moment practicing). Downtime is cumulative; on the first day you learn a few basic phrases, by day 5 you can manage simple conversation with difficulty, by day 10 you can manage a broken but generally complete conversation, and so on. Effective Downtime is halved if you do not have a teacher or speaker to practice with and are self-taught.
  • A few phrases: Just enough to get by. 2 hours to learn three spoken or written phrases.
  • Smattering: This isn't enough to actually carry on a conversation, but will help you understand some basic words. 10 hours to speak or write, 20 hours for both. You can make a Intelligence check to get very general concepts spoken by someone in this language, or to parrot specific common sentences (like “where is the bathroom”).
  • Broken: A broken form of a language takes 20 hours to learn to speak or write, or 40 hours to do both successfully. Broken language allows you to carry on a generally complete conversation without Intelligence checks, although difficult concepts may still be beyond your reach.
  • Accented: An accented form of a language takes 40 hours to learn to speak or write, or 80 hours to do both successfully. This allows you to carry on a conversation, although you will have difficulty disguising your accent or understanding specific dialects.
    • Accented characters with Mimicry in some way or another (the Mastermind's 3rd level class feature, for instance) can convincingly pass as Fluent speakers if they have someone to mimic; however, they still will not understand regional differences in actual language used. (In English terms, one could convincingly mime a regional American accent despite not being fluent, but the difference between soda, cola, and pop would still throw them for a loop.)
  • Fluent: Fluent understanding of a language takes 100 hours to speak or write, or 200 hours to do both successfully. This allows you to understand even odd dialects of a language, to be able to convincingly manage accents (when combined with Performance), and generally to know the language you're speaking or writing.

• Additional Proficiency: Allows you to gain a new Proficiency. This may be with any skill or tool available by RAW as well as additional skills and tools defined as part of Arcydean 5e (for example, Technology or Power Tool variants of standard tool kits.)
  • Tool/Gear/Skill Proficiency:
    • Familiar: Commonly self-taught (at half-normal speed), Familiarity allows you to use a tool, weapon, armor, etc, without suffering the normal penalties for being nonproficient, but without the benefits of proficiency, or adds a flat +1 to otherwise untrained uses of this skill (using a weapon you are otherwise unfamiliar with, for instance). Familiarity requires 20 hours to develop per specific object or skills, or 100 hours to develop for a group of skills (familiarity with heavy armor, for example).
    • Proficient: Generally requires a teacher or some basic familiarity with the concepts involved; allows you to add your proficiency bonus to rolls involving it, and to make certain skill checks that require proficiency. Downtime hours are halved if you are self-taught and do not have a competent person training you, or if you are training with a teacher for a skill not part of your class defaults. Proficiency requires 100 hours to develop per specific object or skill, or 500 hours to develop for a group of skills.
    • Expert: You are uncommonly skilled in this specific application of your skill, and have spent much of your (down)time in refining and honing your craft, above what your level might provide. Provides an additional +1 to proficiency checks. Downtime is halved if you are self-taught and do not have an expert training you. Expertise requires 200 hours to develop per specific object or skill, and is unavailable for groups of skills.
    • Master: You have mastered this specific application of your skill, and have spent months of (down)time in refining and honing your craft, above what your level might provide. Provides an additional +2 to proficiency checks. Downtime is halved if you are self-taught and do not have a master training you. Expertise requires 400 hours to develop per specific object or skill, and is unavailable for groups of skills.
    • Grandmaster: You are extremely skilled at this specific application of your skill, and have spent the majority of your (down)time in refining and honing your craft, above what your level might provide. Provides an additional +3 to proficiency checks. Downtime is halved if you are self-taught and do not have a grandmaster training you. Expertise requires 800 hours to develop per specific object or skill, and is unavailable for groups of skills.

• Feat Development: By training in your downtime, you can develop a Feat with 200 hours of training with someone who already has the feat; halve Downtime gains if you are training by yourself or with someone who doesn't have the feat.

• Attribute Development: By training in your downtime, you can increase an Attribute (to a limit of 20) by +1, with 200 hours of training with someone who has a higher Attribute; halve Downtime gains if you are training by yourself or with someone who doesn't have a higher Attribute.

• Recuperating. Downtime between adventures can also allow you to recover from debilitating injury, disease, or poison. Per 3 days spent recuperating, make a Constitution save vs DC 15. On a successful save, you can choose one: end one effect that prevents you from regaining hit points, or gain advantage on saving throws against one disease or poison currently affecting you. Proper medical care can reduce time or DC, depending on quality of care:
  • Poor: A caretaker watches over you to help your recovery along, providing bandaging or basic treatments. Reduce time required to 2 days. Costs 1 gp per day. Someone proficient in Medicine can provide this level of care for minimal cost (1 sp per day for materials.)
  • Acceptable: A competent physician tends to your needs and provides basic medical treatment. Reduce time required to 1 day. Costs 5 gp per day; a person proficient in Medicine can perform this with one use of a healing kit.
  • Good: The sort of treatment you expect from a modern healthcare facility, this includes people who can directly cure certain problems, and can provide expert care for common maladies. Reduce time to 1 day, and reduce DC to 12. Costs 15 gp per day; requires multiple dedicated Medicine-proficient personnel (but these individuals can treat multiple patients at once.)
  • Excellent: Expensive treatment generally only available in the cities, meant to get people back on their feet quickly and with a minimum of fuss. Most complex problems can be cured, and problems that require more bedrest than intervention are still managed with precision. Reduce time to 1 day, and reduce DC to 10. Costs 30 gp per day; typically provided at hospitals.
  • Advanced: Only available in the largest cities, whether done with magic, psionics, technology or all of the above, this is the best 'basic' care money can buy. Reduce time to 1 day, reduce DC to 10, and choose an extra symptom to cure regardless of success. Costs 100 gp per day; provided at the best hospitals.

• Crafting: Crafting has its own section, which covers everything from the everyman adventurer carving his own quarterstaff out of local timber to monolithic factories producing complex automatons on assembly lines, but the short thing to note is that crafting generally requires Materials and Labor. Using your Downtime for crafting lets you pay off the Labor side of things.

• Professional Work: Despite the adventurer-stimulated economy, most people work for a living and do adventuring less frequently. The economy of Arcydea generally allows even the most unskilled worker to earn the 1 gp per day average required to maintain a modest lifestyle, barring severe employment shortages or other disasters, or provide a poor standard of living for up to five people, or a squalid standard of living for up to ten people. Working in a skilled position generally provides a comfortable standard of living (or a normal standard of living for two people, etc.), while craftsfolk and bards with relevant skills working for themselves generally provide a wealthy standard of living (or comfortable for two people, normal for four, etc.) Want to make more money? Adventure, or start a business!

• Research. With the advanced reach of the ATTN, research generally requires only that you have suitable access to a library of knowledge, time, and an Intelligence/Technology check. The difficulty depends on the DM's assessment of how difficult the information is to find (or if it can be found at all barring blind luck), as well as whether you have to take specific steps to receive the answer you seek (which may require other skill checks). Research may take minutes or days depending on the difficulty of the search.

• Building a Business, Operating a Business. More on these options later.