User blog comment:NicknameMy/Shadow, the spirit of the void/@comment-4881935-20120312050825/@comment-3493296-20120312164321

Shadow Style and Shadow Strike don't work together, you have to choose one for striking out of stealth. And only Shadow Strike has a second part of out of stealth.

The new cost system is a bit like the fury cooldown system on shyvana, but it combines that with the passive. And he is a manaless champ, so his abilities cost nothing. The difference between damage ampiflication and attack damage is that attack damage works against multiple targets while damage amplification only works vs a single target. This should make him harder to play and give him a bit of flexibility.