#0 - Sept. 27, 2009, 5:45 p.m.
And a big thanks to Tashre for this nice post.
A mob that is a skull to you, that is level ?? (a raid boss, essentially), is considered to be 3 levels above you.
Your chance of missing a mob that is 3 levels above you is 17%.
Every ~26.23 points of hit you get, you increase your chance to hit a mob with your spells by 1%. This means that in order to hit a raid boss, you need 446 (rounding up) hit rating to reach your hit cap (the point at which you can no longer miss with any spells). That is a lot of hit, but luckily, there are a few talents and debuffs that will assist you in reaching your hit cap.
The two mage talents are Precision, in the Frost tree, and Arcane Focus, in the Arcane tree.
Precision increases your chance to hit with all spells by 1% per point, up to 3%.
Arcane Focus increases your chance to hit with just Arcane spells by 1% per point, up to 3%.
Arcane Focus and Precision DO stack, so Arcane mages are in luck and can get 6% hit from talents alone whereas Fire and Frost mages are only able to get 3%.
There are also two non-mage talents that apply debuffs to the boss that increases the chance for spells to land on them by an additional 3%.
Improved Faerie Fire, a Balance Druid talent, will apply the hit debuff to the boss whenever a druid debuffs the boss with Faerie Fire.
Misery, a Shadow Pirest talent, will apply the hit debuff to the boss whenever a shadow priest attacks basically.
Imp FF and Misery do not stack with each other but DO stack with both Precision and Arcane Focus, increasing the chance for Frost/Fire mages to hit by a total of 6% and an Arcane mage to hit by 9%.
For Alliance players, it should be noted that Draenei provide the Heroic Presence to their party (note: not entire raid) members within 30 yards, increasing their chances to hit with all spells and abilities by 1%. This aura does not stack.
Arcane mages, employing the use of the standard 57/3/11 spec, will have will have 6% chance to hit from talents.
To reach the hit cap...
Without further aid, they will need 289 hit.
With Heroic Presence, they will need 263 hit.
With Imp FF/Misery, they will need 210 hit.
With both Imp FF/Misery and HP, they will need 184 hit.
TtW/Fireball mages, employing the use of the standard 18/53/0 spec, will have 0% chance to hit from talents (for their fire spells at least).
To reach the hit cap...
Without further aid, they will need 446 hit.
With Heroic Presence, they will need 420 hit.
With Imp FF/Misery, they will need 368 hit.
With both Imp FF/Misery and HP, they will need 341 hit.
Frost and Frostfire mages, employing the uses of the standard 18/0/53 and 0/53/18 specs (respectively), will have 3% chance to hit from talents (for both Frost and Fire spells, with the Brain Freeze talent in mind).
To reach the hit cap...
Without further aid, they will need 368 hit.
With Heroic Presence, they will need 341 hit.
With Imp FF/Misery, they will need 289 hit.
With both Imp FF/Misery and HP, they will need 263 hit.
For Heroic 5 man instances, the bosses are only level 82, which means you'll have a 94% chance to hit them with your spells, further meaning you'll need 6% or 158 hit rating to reach the hit cap.
TtW/Fire mages will need 158 hit to cap.
Frost/FFB mages will need 79 hit to cap.
Arcane mages will need 0 hit to cap.
All unaided. With an Spriest or Boomkin you can cut those numbers in half, and with a draenei you can drop another ~26 hit off too, but it should be stressed that you shouldn't stress about hit so much in Heroic 5 man dungeons. You can go in with 0 hit and do fine; the dps requirements are extremely low since encounters are tailored to players in green/blue quest gear.
Do note that, as long as you're under your hit cap, hit rating, point for point will increase your DPS more than any other stat. Be smart about gearing for hit however. Don't blindly go out of your way for it. If a piece of gear has 60 crit on it and another piece has 20 hit and you're under the cap, don't pick the 20 hit piece. Though hit is more valuable, there's still enough crit to compensate for it's diminished value.
If however you're under the cap and looking at either +30 hit food or +30 sp food, go for the hit food.
Remember, gear smart about it. Act responsibly with your hit rating.
As for the inevitable issue that'll be brought up...
Yes, you may post a parse of a mage who went into Naxx or wherever, 100 hit under the cap and not miss a single spell, but I can show you a parse of a mage with 60% crit only crit 30% of the time. The RNG is a fickle mistress and a very bad thing to try and balance your dps around. Sure, you may forsake hit rating for other stats, and on days where you miss very infrequently or not at all, your dps will be great, but on other days when you miss a ton of times, your dps will be awful. In neglecting your hit cap, you allow your dps to waver from highs to lows, whereas meeting your hit cap will normalize your dps and keep it in the good zone.
If you think I've left anything out, let me know. If any of my facts or numbers are off, please let me know.