Can I use Welder if there are no Fire Energy cards in my hand?
No, you cannot. You must be able to attach at least 1 Fire Energy card in order to use Welder.
Source: TPCi Rules Team (2019-05-09)
If I use Welder and attach a Fire Energy to an Eevee that has the "Energy Evolution" Ability, do I draw the cards for Welder first or search for a Flareon due to "Energy Evolution" first (or is it a choice)?
Since they are simultaneous actions, it is the player's choice of which order they can do this.
Source: TPCi Rules Team (2019-05-09)
If I have Pokemon GX with Abilities in play and the Power Plant Stadium is also play, can I now play Green's Exploration since those Pokemon "have no Abilities"?
Yes, you would be able to play Green's Exploration in that case.
Source: Unbroken Bonds FAQ (2019-04-19), TPCi Rules Team (2019-05-02)
If Wondrous Labyrinth {*} stadium is in play, how many energy are needed for energyless attacks?
Any attacks that normally cost no energy now require at least one energy to be attached when Wondrous Labyrinth {*} is in play. However, if an effect like Persian's "Gathering of Cats" Ability sets an attack's cost to zero energy, Wondrous Labyrinth {*} does not add an additional energy requirement to it.
Source: TPCi Rules Team (2019-05-02)
If I had used Muk & Alolan Muk GX's "Severe Poison" attack that places extra Poison damage counters and in the next turn use Koga's Trap, do they still place the extra Poison damage?
No, they don't. The new, normal Poison Special Condition replaces the old Severe Poison Special Condition.
Source: Unbroken Bonds FAQ (2019-04-19), TPCi Rules Team (2019-05-02)
If I have already played a Supporter, can I then play Lt. Surge's Strategy since I would be able to play 3 Supporters in total?
No. You would have to play Lt. Surge's Strategy as your first Supporter in order to be able to play any additional Supporters during your turn.
Source: Unbroken Bonds FAQ (2019-04-19), TPCi Rules Team (2019-05-02)
Can I play Red's Challenge and fail the deck search?
No, because you are not searching for a specific type of card. It is public knowledge that your deck does have cards in it.
Source: Unbroken Bonds FAQ (2019-04-19), TPCi Rules Team (2019-05-02)
If I'm playing in a Prerelease with 4 Prize Cards, what happens if I have Beast Bringer attached to an Ultra Beast and I Knock Out a GX Pokemon as my first Knock Out?
Nothing happens. The card specifies that you must have exactly 6 Prize cards remaining but you only have 4.
Source: Unbroken Bonds FAQ (2019-04-19), TPCi Rules Team (2019-05-02)
If I use a Trainer card to switch my Active Pokemon that is affected by Poison from Muk & Alolan Muk GX's "Severe Poison" attack and Dust Island is in play, does my new Active Pokemon take the extra damage counters?
Yes, it does. Dust Island specifies that it is affected by "that Special Condition".
Source: Unbroken Bonds FAQ (2019-04-19), TPCi Rules Team (2019-05-02)
If my opponent uses Pokemon Catcher or Escape Rope while Dust Island is in play, is my new Active Pokemon still poisoned.
No, it is not. Dust Island only works when a Trainer card is used to switch your own Pokemon; it does not apply when the Trainer card is played by your opponent.
Source: Unbroken Bonds FAQ (2019-04-19), TPCi Rules Team (2019-05-02)