Can I use Rare Candy on a Scatterbug the first turn of the game or the turn that Scatterbug is played, since "Adaptive Evolution" says it can evolve in those cases?
No, you can't use Rare Candy to evolve in either of those conditions because the text on Rare Candy specifically prevents it.
Source: Scarlet & Violet FAQ; TPCi Rules Team (2023-03-30)
Does Rare Candy override evolution-preventing effects such as Archeops' "Ancient Power" Ability?
Ancient Power does not allow you to use a Pokemon's attack or play a Trainer card to evolve your Benched or Active Pokemon, unless the Evolution card you would be putting into play comes from somewhere other than your hand. So Rare Candy cannot be used while Archeops' Ancient Power Ability is in effect.
Source: Noble Victories FAQ (2011-11-17), PUI Rules Team (2011-11-17), PUI Rules Team (2011-11-21)
If the Broken Time-Space stadium is in play, can I use Rare Candy on a Basic Pokemon that just came into play this turn?
No, the wording of Rare Candy specifically says "you can't use this card during your first turn or on a Basic Pokémon that was put into play this turn". Broken Time-Space does not allow you to override that.
Source: PUI Rules Team (2011-06-09)
The wording of Rare Candy is now as follows, "Choose 1 of your Basic Pokémon in play. If you have a Stage 2 card in your hand that evolves from that Pokémon, put that card on the Basic Pokémon. (This counts as evolving that Pokémon.) You can't use this card during your first turn or on a Basic Pokémon that was put into play this turn." So now it can't be used on your first turn, and it can't be used on a Pokémon played this turn.
Source: TPCi Announcement (2011-04-11), PUI Rules Team (2011-05-05)
Can I play Rare Candy on a Basic Pokémon to evolve it into a Stage 1 even though that Pokémon could evolve that turn normally?
No, this is no longer permissible [per BW rules changes].
Source: PUI Rules Team (2006-01-05), TPCi Announcement (2011-04-11), TPCi Announcement (2011-05-05)
Can I use Rare Candy on [my] first turn of a game (when Pokémon are not normally allowed to evolve)?
No, this is no longer permissible [per BW rules changes].
Source: PUI Rules Team (2004-07-22), TPCi Announcement (2011-04-11), TPCi Announcement (2011-05-05)
Can I use Rare Candy on a Pokémon's first turn in play? For example, can I place down a Wurmple and then use Rare Candy on the same turn to evolve it into Dustox or Beautifly?
No, this is no longer permissible [per BW rules changes].
Source: PUI Rules Team (2003-09-11), PUI Rules Team (2004-07-22), PUI Rules Team (2011-04-11), PUI Rules Team (2011-05-05)
Can I use Rare Candy to evolve from Dome Fossil to one of the Kabutops from older expansions that evolve from Mysterious Fossil?
Since Kabutops can evolve from Kabuto of any expansion, you may use Rare Candy to evolve either Dome Fossil or Mysterious Fossil into any Kabutops, regardless of expansion.
Source: PUI Rules Team (2008-05-22)
If you use Rare Candy to evolve a Pokémon, and the evo card has a "Coming into Play" Pokémon Power (such as Dark Crobat), does that coming into play power get activated?
Using Powers, Attacks, or Trainers that let you put a Pokémon in the game from your hand will allow coming into play Powers to activate. This is a reversal from previous rulings.
Source: PUI Rules Team (2003-10-23), PUI Rules Team (2005-04-14)
Can I evolve Dratini in play to Dark Dragonite by using Rare Candy?
Yes. [This is true as long as there is a normal evolutionary path between the basic and the Stage 2 "Dark" Pokémon.]
Source: PUI Rules Team (2005-02-10)