Formulas and Game Mechanics

Spellcasting

Chance to Cast

( Gathered from Wilki's statements in http://boards.stratics.com/php-bin/uo/showflat.php?Cat=&Number=7087151 )

• ChanceToCast = ( ( Skill - ( Difficulty - ( Focus / 2 ) ) ) / Focus )%
• Chance to Cast can never be negative, nor over 100%.
• The Minimum Skill Requirement to cast a spell exists two ways:
  • For Chivalry, Magery, and Necromancy: MinimumRequirement = ( Difficulty - ( Focus / 2 ) )
  • For Everything Else: MinimumRequirement = ( ( Difficulty - ( Focus / 2) ) + ( ( Focus * 5 ) / 20 ) )

Definitions

• Skill: The caster's skill level.
• Difficulty: the point where you have 50% to succeed
• Focus: How wide the "window" is between 0-100%, centered on the difficulty value
• Minimum Requirement: Minimum skill level required before spell can be cast (even if the chance to cast is above 0)

Values

Difficulty

Chivalry

• Cleanse by Fire: 30
• Close Wounds: 25
• Consecrate Weapon: 40
• Dispel Evil: 60
• Divine Fury: 50
• Enemy of One: 70
• Holy Light: 80
• Noble Sacrifice: 90
• Remove Curse: 30
• Sacred Journey: 40

Magery

• 1st Circle: 0
• 2nd Circle: 15
• 3rd Circle: 29
• 4th Circle: 43
• 5th Circle: 58
• 6th Circle: 72
• 7th Circle: 86
• 8th Circle: 100

Focus

• All Bushido: 50
• All Chivalry: 50
• All Magery: 40
• All Necromancy: 40
• All Ninjitsu: 50
• All Spellweaving: 50

"Plain English" Version

• Magery and Necromancy spells require 20 skill points above the minimum requirement to be cast 50% of the time, and 40 skill points above the minimum requirement to be cast 100% of the time.
• Chivlary spells requires 25 skill points above the minimum requirement to be cast 50% of the time, and 40 skill points above the minimum requirement to be cast 100% of the time.
• Bushido, Ninjitsu, and Spellweaving spells require 12.5 skill points above the minimum requirement to be cast 50% of the time, and 37.5 skill spoints above the minimum requirement to be cast 100% of the time.
• All minimum requirements except for magery are listed in game. Magery minimum requirements can be found on UO.com: http://guide.uo.com/magic.html