Runes of Magic US / AU

Source code

As there are often questions  about the healing mechanics, decided to   post again the formula ( which  apart from some bugs during different   patches, hasn't really changed  since ch 2).

[B]Burst Heals:[/B] (final result of burst heals gets random  bonus   multipliers +6%/-6% so in fact the result is within 94-106% of  the   calculated value)

[B][MagicPower] x (CastTime) x (ReceivedHeals) x [(Wisdom x 0.3 +    mDamage x 0.5) x (IncreasedHealing) + HPI] + (SkillHeal x Received  Heals   x IncreasedHealing)
[/B]
To translate different multipliers into smth easier to understand:
- Magic Power Increase - global increase of the final damage/heal    output, typical examples Vahtos/ Juggler sets. Bugged at start of ch3    (no effect on burst heals) but was fixed back soon. Can raise the cap    for regens. Total increase is a bit less than 15%/10%, as Skill Heal is    added separately at the end.
- Cast Time - like most RoM skills, you have time of cast spells as multiplier: 2 sec - x2, 3sec - x3
- ReceivedHeals - buffs that increase heals received by target - pet    passive, Curing Seed, Lunar Halo, Healing Salve. They increase the    amount of heals by %
- Increased Healing - usually the class passives that increase your    heals - Prayer, Pure Healing, Divine Incarnation, as well as food (but    as mDamage food gives better results, usually out of calculations).  Note   - those don't affect your HPI. For example 1.35 multiplier from  Pure   Healing only applies to the rest of equation, so the total  increase is   far less than 35%
- Wisdom - every healing spell has cap above which Wisdom is ignored for    healing purpose. Really notable with Priest - GH at ~4k and UH ~7k.    Druid has it easier - Recover ~4.5k, MEF ~ 13k (11k is no NP), Restore    Life/Heal ~11k are not really used in combat but no harm to mention  them   too.
mDamage - total mDamage you get from your weapons, gear, buffs. Note    that there is some gear (chests) that gives '+ magic damage [U]bonus[/U] points' - unlike '+ magic damage points', those only provide static increase to your final damage and are of no use for heals.
HPI - Healing Points Increase that you get from your healer gear (D/S can get a bit of HPI from 40 elite)
SkillHeal - the value added by the skill itself.

[B]HoT Heals:[MagicPower] x (CastTime) x (ReceivedHeals) x [(Wisdom  x   0.3 + mDamage) x (IncreasedHealing) + HPI] / ticks + (SkillHeal x    Received Heals x IncreasedHealing)
[/B]
Main differences: mDamage has double value with HoTs; HoTs can't crit;    no Wisdom cap, but 24015 cap for regens (a bit over 26k with  Juggler's),   since ch3 mechanic was often bugged - now you get all the  ticks but   they start with 1 tick delay.

Example how calculations go (random numbers):
D/S 9k mDmg, 15k Wis, 12k HPI casts Recover on target with Lunar Halo buff active:
burst:[1.00] x 2 x 1.05 x [(4500x0.3 + 9000x0.5) x 1.35 + 12000] + (600 x 1.35 x 1.05) ~ 43k non-crit
regen: [1.00] x 2 x 1.05 x [(15000x0.3 + 9000) x 1.35 + 12000] / 7 + (272 x 1.35 x 1.05) ~ 9.5k per tick
life link (Life Guide) in this case as all multipliers are the same is 7/3 of Recover ticks ~ 22.5k per tick

[B]Crit rate:[/B] general formula calculates crit resistance of target and then depending on your rate determines the %. 
[B][I]CritResist=(60*lvl + 600)
[/I][/B][I]if[/I][B][I] cRate > cResist/2 [/I][/B][I]then[/I][B][I]100 * (cRate - cResist/4) / cRate
[/I][/B][I]else[/I][B][I] 100 * cRate / cResist[/I][/B]

As we see up to 50% things go linear, above 65% rate gives very    diminishing returns. Just to complete the theme to add that bosses have    extra crit Resist, skills that add to crit% in fact reduce crit Resist,    and that every level of difference additionally puts +/- 3%    bonus/penalty to your final score.

But as we are speaking about healing - all that is important is healer    level (for critResist - 4800 at 70) and his Rate. For example 2400    should give 50%, 3000 - 60%, 3600 - 66%. Ofc those numbers change with    every new lvl cap but this helps plan your gear to keep crit above 60%.

Though I left RoM for good , hope that re-posting formulas may help new healers who enjoy the game.