Skills

A player uses a skill from its skill window or a macro; a script tries a mobile at a skill with skill.check, and the try may raise the skill. Twenty-one skills ship a script (scripts/skills/): Hiding, Stealth, Snooping, Detecting Hidden, Anatomy, Animal Lore, Animal Taming, Evaluating Intelligence, Forensic Evaluation, Tracking, Spirit Speak, Arms Lore, Peacemaking, Provocation, Discordance, Stealing, Meditation, Item Identification, Taste Identification, Begging and Poisoning; see Hiding and the other skill scripts there. The rest of the game calls the same check as it is built.

Using a skill

The client sends a text command (packet 0x12, kind 0x24) whose text starts with the number of the skill, as 21 0 for Hiding.

A dead character is refused with a message (cliloc 1019048), the staff included.
A prisoner of the jail reads “You may not use skills in jail.” (message 30168); the staff is never refused.
A character still waiting after its last skill reads “You must wait a few moments to use another skill.” (cliloc 500118), once a second at most.
The script of the skill runs: on_use(user) of the table named after the skill in scripts/skills/<skill>.lua, with the names of data/skills.toml (hiding, animal_lore).
A skill without a script answers “That skill cannot be used directly.” (500014), and asks no wait.
The character then waits before another skill: the number on_use returns, in seconds from 0 to 3600; when it returns none, the delay of the skill in data/skills.toml; one second when the file gives none either. An on_use that calls wait() is still running when the wait is set: it asks the delay of the skill, 10 seconds at least, and what it returns later is not read.

A skill script may define other functions that the server calls from elsewhere: on_snoop(user, owner, container) in snooping.lua runs when a player double clicks someone else’s container, instead of opening it.

animal_taming has delay = 30.0 in the toml, but its script always returns 1 second, so that value is never used.

The wait is of the character and one for all its skills, as in ModernUO. It is not saved: it does not outlive a restart.

-- scripts/skills/hiding.lua
hiding = {}

function hiding.on_use(user)
    if skill.check(user, "hiding", 0, 100) then
        mobile.set_hidden(user, true)
    end
end

[[skill]]
id = "hiding"
delay = 10.0

The scripts are loaded at startup, as the item scripts are; the other kinds of text command (casting a spell, opening a door, an action) are read and not acted on yet.

The check

skill.check(who, skill, min, max) tries a mobile at a task: min is the points at which the task can just be begun, max those at which it never fails.

Points of the mobile	Result	Can it teach?
Below `min`	Fails	No
At `max` or above	Succeeds	No
In between	Succeeds with the chance `(points - min) / (max - min)`	Yes

So a task too hard or too easy teaches nothing, as in ModernUO.

The gain

A try in between, passed or failed, may raise the skill of a player. NPCs never learn.

Below 10.0 points a skill always learns.
From 10.0 on, the chance is ModernUO’s: the mean of the room left under the total cap and under the cap of the skill, then the mean of that and of how hard the task was (a pass counts half of what was missing to the certainty, a failure a fifth), times the gain_factor of the skill in data/skills.toml; never less than one in a hundred.
A skill up to 10.0 points gains from 0.1 to 0.4 points at a time, above it 0.1.
A skill at its cap (100.0) does not rise, nor one whose lock is not up.
The total of a player’s skills stops at ultima.skills.total_cap (700.0 points). The nearer the total is to it, the more often a gain first lowers another skill whose lock is down by the same amount; at the cap, a skill rises only when one could be lowered.
A game master sets a skill by hand with skill; the total cap does not apply to it.

The locks

Each skill has a lock, up for every skill of a new character: the arrow beside it in the skill window. The player moves it and the client tells the server (packet 0x3A), which keeps it with the skill and saves it.

Lock	The skill
Up	May rise when it is tried.
Down	Does not rise, and may be lowered to make room for another that rises when the total is at its cap.
Locked	Does not rise and is never lowered.

A skill or a lock that does not exist is ignored.

ultima.skills.gain_enabled = false stops every gain: the checks still pass and fail.

The stats

A successful check of a player can also raise strength, dexterity or intelligence, as ModernUO’s classic rule, whether or not the skill itself rose (a failed check never does). The fields str_gain, dex_gain and int_gain of the skill in data/skills.toml say how much the skill favours each stat; a stat whose number is 0 is never tried by that skill.

For each stat the skill favours and whose lock is up, a roll with the chance gain / 33.3 (a gain of 0.8 is 2.4%).
A stat that passes is tried once in stat_gain_minutes (10): the wait starts when it is tried, even if nothing rises. It is kept in memory, not saved: after a restart a stat can be tried at once.
The more the three stats add up to near stat_cap (225), the more often the player gives way: one point is taken from a stat locked down (above 10 points), the lower of the two when both can. Once the total is at the cap it always gives way.
If the total is then below stat_cap, the stat is up and below stat_max (100), it rises by one.

The maximum of its bar moves with it: strength the hit points, dexterity the stamina and intelligence the mana, and the player sees the whole status again. NPCs never gain stats.

Strength, dexterity and intelligence have a lock each, as the skills do, saved with the character: the arrows beside them in the status window (0xBF subcommand 0x1A from the client, and 0x19 to the client at login and each time a lock changes).

Lock	The stat
Up	May rise when a skill is tried.
Down	Does not rise; gives a point away when another rises and the total is at the cap.
Locked	Does not rise and is never lowered.

The wait of a stat is kept by character in memory, so logging out and in does not skip it; a restart does. The three columns (str_lock, dex_lock, int_lock) are part of world.mobiles.

Trainers

A vendor, a healer or a stablemaster teaches the skills it has at 60.0 or more, as ModernUO’s trainers do. The skills are those of its mobile template, so a vendor teaches whichever skills rolled that high. Bankers do not teach: gold dropped on them is deposited.

Ask. The context menu of the NPC has a Train entry for each skill it teaches and the player knows less of, from 8 tiles (12 for the stablemaster). Saying train within 4 tiles, alive, has the NPC list the skills it teaches, or say it has nothing to teach.
Price. The NPC teaches up to a third of its own value, 42.0 at most and never above the player’s cap for the skill. Picking an entry makes it say the price: 1 gold for each tenth of a point, so 10 gold for a whole point (420 gold for 42.0), and that for less it teaches less. The quote lasts until it is paid, another one is given, or the session ends.
Pay. The player drops gold on the NPC, from 2 tiles. The skill rises at once by one tenth of a point for each gold piece, up to what was quoted; only the gold needed is taken, and the rest of the pile stays with the player. A drop without a quote from that NPC, or of anything but gold, goes back.
Refused. The player already knows as much as the NPC would teach (thou knowest all I can teach) or more; the skill is not locked up, or the total cap (ultima.skills.total_cap) leaves no room even after lowering the skills locked down, which give way in the order of the skills; the player is dead. A gold drop that can no longer teach gets the same answer, and the quote is dropped.

A script gives an NPC these lessons with the trainer module and common/training.lua; shopkeeper.lua, healer.lua and stablemaster.lua already do. trainer.skills(npc, player) lists the skills, trainer.quote(npc, player, skill) quotes a price and trainer.pay(npc, giver, item) takes the gold, which is what an on_drag_drop answers.

Guildmasters

The twelve guildmasters of ModernUO (bard, blacksmith, fisher, healer, mage, merchant, miner, ranger, tailor, thief, tinker and warrior) are mobile templates, a man (m_<trade>_guildmaster) and a woman (f_<trade>_guildmaster) for each, and an npc list of the trade (<trade>guildmaster) that picks one. They are made by moongate-convert modernuo-guildmasters from ModernUO’s classes: the title (the blacksmith guildmaster or guildmistress), the skills of the trade, the main ones between 80 and 100, and the guild, and what they wear and carry for the trade: the blacksmith an apron or a ringmail chest, a bascinet and a hammer, the mage and the healer a robe (in a blue or yellow hue) and the mage a staff. The kryss or dagger of the thief has no item template yet. They are vendors like the others, so they teach what they know (Trainers); only the blacksmith’s sells, as in ModernUO. The ModernUO spawns place them in the towns.

A guildmaster takes members for the guild of its trade. A player says the guildmaster’s name and join or member within 2 tiles to hear the price, 500 gold (the guildmaster speaks to that player only, over its head), and drops exactly that gold on it to join. A player belongs to one guild at most (the guild is a saved prop of the character) and is told when it is a member already or of another guild. The thieves’ guild asks for no kills and Stealing 60.0 (the thieves’ guildmaster of the towns of UOX3 is a guildmaster too, now). Saying the name and resign or quit leaves the guild, no sooner than a week after joining. The miner’s guildmaster names no guild in ModernUO, so it only teaches. A membership has no effect yet: nothing reads it. The age and the playing time ModernUO asks of a new member are not kept.

The template field npc_guild (blacksmiths, thieves…) makes an NPC a guildmaster, and the npcguild Lua module (of, member, quote, is_join_payment, join, resign) with common/guild.lua gives its script the words and the gold.