On my last turn, I attacked with Zebstrika's "Coordinated Bolt" attack. If I use a different Zebstrika's "Coordinated Bolt" this turn, will it do extra damage?
Yes, that would work.
Source:
Chilling Reign FAQ; TPCi Rules Team (2021-06-17)
On my last turn, I attacked with Blitzle's "Thunder Spear" attack. If I evolve it into Zebstrika this turn and use "Coordinated Bolt", will it do extra damage?
Yes, Zebstrika is not the Pokemon that attacked last turn; Blitzle was your other Rapid Strike Pokemon that used an attack on the previous turn.
Source:
Chilling Reign FAQ; TPCi Rules Team (2021-06-17)
On my opponent's last turn, they flipped heads for Diglett's "Dig" attack. If I use Blissey V's "Blissful Blast" attack on my turn, would I be able to attach Energy cards from my discard pile?
No. Since Blissful Blast did no damage due to Dig, you cannot get any Energy cards from the discard pile with Blissful Blast.
Source:
Chilling Reign FAQ; TPCi Rules Team (2021-06-17)
If my opponent uses Guzzlord's "Red Banquet" attack and my Active Pokemon with Big Parasol attached gets KO'd, does my opponent get to take an extra prize for "Red Banquet" or not?
Big Parasol prevents all effects of attacks from your opponent's Pokemon done to your Pokemon; but taking an extra prize is a game effect, not "an effect done to your Pokemon", so your opponent gets to take the extra prize.
If my opponent takes a prize and then I use Naganadel GX's "Injection GX" attack to add a prize to my opponent's Prize Cards, would my Dubwool V's "Revenge Blast" attack do only 120 damage because the number of prizes in my opponent's Prize Card area has increased? Or does it do 150 damage (120+30) because the opponent has already taken that prize (even though it is now back in the prize pile)?
Revenge Blast is based on the number of prize cards TAKEN, so even though the Prize Card gets put back into the opponent's area it still counts as +30 damage for Revenge Blast.
If I use Victini V's "V Bullet" attack or Victini VMax's "Max Victory" attack and my opponent’s Active Pokemon is a VMax Pokemon, does the attack do more damage?
Yes, per the Rule Book, Pokemon VMAX are always considered to be Pokemon V.
Source:
Battle Styles FAQ; TPCi Rules Team (2021-03-18)