[Guide] Critical hits on openers

People <3 big critz. We all do. Assassins have 3 ways of increasing their critical hit chances which are:

Dark Inspiration +25% chance to crit on opener - Swift Strikes
Sense Weakness +25% chance to crit on opener - Slow Death Strikes, Grimm Corruption, Lethargy, Impede life,
Opportunistic strike +500% chance to crit on opener - any non-feated combo

So what "opening attack increase critical chance" really means?

Combo critz and critz

First of all lets get two things straight: in combat regular combo critz are shown as orange. You will see all sort of big numers flying by as you go through your combo animation. The regular critz are shown in white. Go jab someone with a dagger - sooner or later a bigger white number with pop up on your opponent's left side. That is a regular crit. As for "opening attack" or "opener" crit it is the same white damage, but it goes of after you pressed your combo button.

Lets say you have grim corruption which is one step combo: if you press your button that grim corruption is bound to AND your target is within your reach the combo step icon with light up in a green color, which means "opening attack hit the target" and "there is no damage penality if you land your grim corruption by pressing the combo step button".
That first combo damage is called "opener". Sometimes the openers will crit with extra damage, but if you want to see a lot of that happening I suggest you get one of the above mentioned feats.

Sense weakness + Dark inspiration

They are basiclly the same feats, but for diffrent trees and diffrent combos. Those are passive, but NOTICABLE crit chance increasing feats. Once you have those you will see your openers getting those critz a lot more often. Dark inspiration is a lot better than sense weakness for one simple reason: it buffs up your Swift Strikes combos and those are used all the time, unlike SDS and GC which both have horrible cooldown. Just rotate diffrent ranks of SS to see those numbers rolling. Sense weakness on the other hand can grant you "crit chain" when combined with Opportunistic strike (more on that later).

pros: great, cheap passive damage increase for your combos
cons: they won't crit if you really need them to ;p

Opportunistic strike

Despite its description (+500% to crit?) it just critz all the time (like 500% should..). Using OS gives you 15s buff that will work on your next opener, so if you miss it you still will have time to benefit from the buff by using another combo.. There is just one trick: it won't work on combos that are gained through feat trees so no critz for Death Whirlwind, Blindside, Anthropy ,Snapkick or sabotage armor.

pros: great, cheap passive damage increase for all combos. Works when you need it.
cons: way too long cooldown (1m), won't work with feated in combos

How to take maximum benefit from high critz chance?

Crit chain

Since your openers have such hight crit chance it won't be uncommon for you to see them criting one after another. If you go Grim Corruption (crit) + Impede Life (crit) + Swift Strikes (crit from OS) you will see that you have quickly builded up a lot of extra damage with fast combos (both GC and impede are one step combos). If you do those while buffed with Lotus overdose you can get quite the burst of damage.

AOE damage

Critz will go off on any nerby opponent that is within your reach. Opening with Impede life, which has nice cone efect, will first apply crit on several opponents and then damage and debuff them with aoe.

AOE debuff

We can all agree that lethargy sucks, no doubts about it. This crap is still one step combo that benefits from sense weakness and applies poor excusse for a debuff (-6% to melee which is marginal at best). Still this is a very fast combo and when confronted with several mobs it will be benefitial for you to damage them with oppener and debuff quickly before going with Swift Strikes

PVE and PVP applications

All three of those feats are valid in both PVE and PVP. Skipping on those in any builds is stripping yourself of bonus, burst damage that might save your hide more than once. They are all 1 feat points and should be squized into your build.