If I have only 1 card left in my deck and my Pokemon with the Amulet of Hope tool attached is KO'd do I have to take that card and put it into my hand?
Yes. You must take at least 1 card with Amulet of Hope when it applies.
Source:
Surging Sparks FAQ; TPCi Rules Team (2024-11-07)
If Pikachu ex has full HP and a Lively Stadium is in play, and Roaring Moon ex uses its "Calamity Storm" attack and discards the stadium, will Pikachu ex's "Resolute Heart" Ability prevent it from being KO'd leaving it with 10 HP remaining?
No, it won't. Calamity Storm does 220 damage and that many damage counters are placed onto Pikachu ex, so it no longer has full HP at this point due to Lively Stadium and the "Full HP condition" is not met in order to trigger Resolute Heart; then the stadium is discarded, returning Pikachu ex's maximum HP to 200, and therefore Pikachu ex is KO'd. However, if Calamity Storm does 230 damage (for example, if Roaring Moon ex has a Vitality Band attached), Resolute Heart would work; the attack places 230 damage onto Pikachu ex, thus meeting the "Full HP condition" in order to trigger Resolute Heart; then the Stadium is discarded, and Pikachu ex survives with 10 HP remaining (190 damage on it).
Source:
Surging Sparks FAQ; TPCi Rules Team (2024-11-07)
What happens if I use Area Zero Underdepths to replace Sky Field, or vice versa? Does either player need to discard Pokemon because the Sky Field/Area Zero Underdepths stadium left play, or is the transition instantaneous?
As long as you meet the required criteria of the new stadium you would not have to discard any Benched Pokemon since one stadium's effect is replacing the other simultaneously.
If my opponent flips heads for Shuppet's "Enveloping Shadow" attack, can I still play Antique Dome Fossil or Antique Helix Fossil since they say to "Play this card as if it were a 60-HP Basic {*} Pokemon"?
No you cannot, because it is still considered to be an Item Card while in your hand.
If Roaring Moon ex's "Calamity Storm" attacks a Pokemon without a Rule Box and chooses to discard the Neutralization Zone stadium, is the damage neutralized before discarding the stadium, or does the damage happen after discarding the stadium?
The *choice* is made to discard the Stadium and damage is calculated, however Neutralization Zone stadium prevents that damage from being done. After that the Stadium is discarded.
If Haxorus uses its "Bring Down the Axe" attack while Temple of Sinnoh is in play and there is a Mist Energy attached to the Defending Pokemon, does it knock out the Defending Pokemon?
Yes. Even though Temple of Sinnoh turns off the text portion of Mist Energy, it still remains a Special Energy Card and meets the requirement for Bring Down the Axe.