Willpower and Regen could not be more different - WP you just turn on toggles and go, whereas Regen you have to click lots of stuff, and monitor your health bar/when dmg will be incoming
Power Siphon stacks by using other powers. Example: You click PS. You then click Quick Strike. Using QS stacks it a single time. Then you use smashing blow which stacks it a second time. And so on and so forth.
Here is how Power Siphon works, evey Kinetic attack used after PS is clicked will grant you a damage buff (you can monitor it, in game, in the combat attributes of your powers tray) this buff can ramp up to 156% after the fifth Kinetic attack power lands. That is what is meant by stacking it five times, a sixth attack will not give any bonus. Mind you, this is all relative to PS being active, once PS ends you gain no damage bonus from attacks. Hope this helps.
Edit: I failed to mention that Concentrated Strike does not have a chance to crit, instead it has a chance to instantly recharge PS. But know that if you use PS and then again while the original PS is in effect all you have done is restart it's timer. It will not let you start stacking the damage buff passed five times.
Longtime Brute (lotsa 50s), rare Scrapper (highest mid-30s). But enough about me.
I just started a Kinetic/Regen Scrapper. I have little idea what I am doing, but I kind of like the guy.
What is it with Kinetics, how does the build up thing work? It says you can stack it up to 5 times, but that makes so little sense to me I feel like either I am drunk reading it, or they were drunk writing it. I'd be lucky to stack it twice with a buttload of recharge, and if I tried to stack it 5 times I'd really not be attacking at all, I'd just be spamming build up. Seems counter productive. But just as a one-off no stacking thing, is it worth it? (I know most build ups are, but I am used to 2 minutes of Rage, so kinda unimpressed by a few seconds of glory.)
Anybody got some decent experience with Kinetics they can share? My last main was a Willpower brute, so I think I got a grip on Regeneration, a little more manic/button mashy, but Willpower is the essence of not pay attention secondary, so ya gotta expect some work sometimes.