I'm using a single lightsaber on my main character (that's how I roll). I just picked up a crystal which doubles the critical threat range of the saber (to 17-20). My question is this: what is the critical threat range of an attack using master critical strike (my attack skill)? It says that it quadrouples the critical threat range of the attack, but a quick glance at the log shows that (unless I am mistaken... which is entirely possible) rolls are not triggering crits as I expected. Can anyone explain?
Also, right now I'm using a krayt dragon pearl and the double-critical-threat-range crystal in my lightsaber (again with master critical strike). I also picked up the +2-12-on-crits crystal, but I figured that I should keep the krayt for the +attack. Any advice on which crystals would be best for this setup?
Threat range boosting effects only scale additively, not multiplicatively. The easiest way to think about it is to use the base critical threat range of your weapon as your 'threat unit' (a term I just made up), figure out how many threat units your attack pattern generates.
Using your single bladed saber as an example, your threat range is 19-20, which give you a 'threat unit' of 2.
The base threat range of the weapon gives you 1 unit.
Keen "doubles" this, adding a threat unit, for a total of 2.
Each level of the critical strike chain adds another unit, for a total of 5.
5 units times the threat range of 2 gives you a total threat range of 10, so using a keened saber and Master Critical strike, you score a threat on rolls of 11-20, or 50% of the time.
The way the game calculates things, if your initial roll scores a threat, then you make another attack roll. If it hits, then the hit is a critical hit, and does double damage. It is possible to miss on the follow-up attack roll, so not all threats will work out to be critical hits.
As for which crystals to use, generally the "Massive Criticals" effect isn't as desirable as a straight-up increase in damage, but without knowing the specific stats of your character and what your other crystal options are, it's impossible to say for sure.
--- So if I fight the good fight will hairlines recede? Will lines deepen in face to craft a look of defeat?
Thank you, dronemc... your explanation was very clear.
Indeed, additive effects of multipliers are fairly common in games... I should have guessed. I had no idea about the second attack roll for critical hits, however. This makes the critical strike attack style somewhat weaker than I had expected (as compared to flurry). I'm not sure that it was a good move, given the massive defense penalty.
This second roll also makes the Krayt Dragon Pearl a little better given it's +3 attack bonus.