Source? That seems wrong as it opens up the possibility of using the same power multiple times if it can be used as an interrupt and a standard or move.
This one is more of something called common sense really... when do you deal damage, when an attack has been found to have hit. When do you say that the attack is "resolved" after all damage has been assigned. Well, in same sense, a power is not considered "used/finished" until the effects of it have been tallied up. I would not think you would need a rule to discover that... to me it would be like saying someone needs a source to prove that breathing is necessary... umm, ok, yeah... "it's done when it is done" seems slightly obvious.
There aren't any cards, there isn't a discard pile, and there isn't a stack to temporarily place your power on.
Not even remotely. You don't lose if you can't draw a power, you don't have an upkeep, you don't tap anything, you don't have cards, there isn't any concept of discard or stack, summoning doesn't have summoning sickness, you can't drop artifacts into existence from nowhere, you can't use summons to block, they don't trample, targeting rules are completely different, regeneration is completely different, protection does not equal resistance, invulnerable does not equal immunity, concealment does not equal shadow etc. etc.
Well, unfortunate for me, fortunate for you... the search function has been limited to only paying subscribers of this forum... which I am not currently.
From the start of this edition until now, there have been off and on side comments from several people (not just on this board) about the likeness of this Edition and: MTG, Various MMO's, and other sources.
I never once said this game IS magic the gathering, for one. Also, many people DO, in fact, use cards... and REALLY? There aren't any cards?? Then must be my imagination that WOTC is selling... oh yeah, POWER CARDS.... wow... and owned by same company selling both games, no way they would ever somehow utilize similar concepts...
When players use the cards, at least in my group... it is eerie how they either turn them to the side, flip them over, or "discard" them... almost as if it is natural to do so...
I don't understand why you chose to target me, and speak to me harshly (because yes it came off as insulting), and with, what I take as, so little to back you up. Along with having a similar quality to trolls on other boards, "Source?" Seems to be a very common question used to try and incite issues...
Anyway, for lack of anything definite in PHB, a power is used when it's used so it could recover itself.
_My Opinion_: This statement is wrong. Do what you will though.