Something odd has been happening with crit and crit block. In a PVP tonight we got hit with several waves of crit from fire wizards and our crit blocks didn't crit block! What's up with 3 wizards with 115 crit block and 120 crit block having only maybe 1 block on one wizard out of about 4 critical spell waves?
I read through the forums on Wizard101.com and with all the questions about crit and crit block they were all answered very cryptically. The thread master even closed the thread after specifically dodging pretty much all the questions about how it actually works. But a number of astute wizards seemed to be insistent on a mathematical formula which doesn't quite bear out in practice. The typical guesstimate is that every 5 points of crit give you a 1% + chance of critical hit. This would mean, if true, that for 100 crit you have a 20% chance of getting a critical hit. But this doesn't explain why fire wizards can crit pretty much every hit at around 170 crit which should only crit one out of every 3 tries. It also doesn't explain why crit block used to be almost rock solid at 110+. There was a time when 100+ crit block blocked nearly all of the time. Now that seems to not be the case at all. So it leads back to my paranoid theory that we are looking at an adjusted percentage either from a recent game update or a synergistic effect between spells on the PRNG (pseudo random number generator).
Since Wizard hasn't announced adjusting crit and crit block in the update notes of late I have to go deeper down the rabbit hole and say that it's linked somehow to infallible or that crit block itself is being pierced by shield pierce stats. Our PVP opponents seemed to be un-phased by the fact that were were constantly critted without block. Either we were on the receiving end of the mother of all bad virutal dice rolling streaks in history or there's something to this theory. (my luck has been known to be bad from time to time... my eyelid still twitches when I hear the word "bolt")
I asked some of my savvy pvp friends and they didn't answer yet as to whether or not they've heard that pierce stats or infallible work this way. I'll keep asking around, but based on the sudden extreme popularity of infallible domes in PVP I'd say that people have sensed that it's a game-changer.
Back to the question of the formula for crit and crit block my sense is that it's a sliding scale even if not by intent. If you play a fire wiz and an ice wiz you'll know what I mean. I think that the formula is probably something like this:
if (crit% is less than 100) then crit-chance = crit/500
**** this is a straight 1/5 ratio or maximum of 20% or 100 crit = 20% chance****
if (crit% is greater than 100) then crit-chance = crit / 400
**** this would mean that 200% crit would give a 50% chance ****
I'm sure this would work into an equation that would accommodate the sliding scale from noob crit up to the super-crit of the 160+ range but I'll let you noodle on this for a bit.
Historically, crit block seemed to be the exact inverse of this. A crit block of 100 would give you an 80% chance of blocking the spell. Based on tonight's experiment something drastically reduced those odds. I won't rest until I get some answers.
Let me know what your experience shows!
Until then, good luck in your battles.
p.s. Jose had a good point that the new higher gear seems to behave a little differently than the celestia in terms of crit per the numbers.
Also Eric has a theory that crit block gets minused from someone's crit number and then there is a chance given the remainder of crit for you to get nuked. If people are actually getting into the 200+ range and a good block number is 112+ then you have a fair chance of getting hit. I don't think it should be that you get critted 4/5 hits without any block. That seems excessive in any probability model but until we find a link between infallable and crit block failure then this may be the best theory proposed so far.