If an evolved Pokemon is Knocked Out with Rescue Scarf attached to it, do you get to put all of the evolution stage cards and Basic Pokemon card back into your hand, or just the highest stage Evolution card?
All of them go to back into your hand.
Source:
Dragons Exalted FAQ (2012-08-23), TPCi Rules Team (2012-08-23)
Can I use Heavy Ball to look for a LEGEND Pokemon half?
No, you cannot. The Retreat Cost is only printed on one half of the LEGEND Pokemon. If it is printed on both cards, then it is a common attribute for both pieces; but since it is printed on only one half it only applies to the LEGEND Pokemon when both pieces are in play.
If Cinccino with the "Smooth Coat" ability also has "Rocky Helmet" attached to it, can I choose to activate Rocky Helmet first, and then flip for Smooth Coat?
You would need to know whether Cinccino takes damage or not in order for Rocky Helmet to work, so in this scenario you would have to flip for Smooth Coat first.
If Rocky Helmet is attached to a Pokemon with an effect such as Donphan's "Exoskeleton" Poke-BODY or a Defender attached, will an attack that normally deals 20 or less damage trigger the effects of Rocky Helmet or not?
If the net effect of the attack results in zero damage done to the Defending Pokemon, Rocky Helmet does not trigger.