064 167 pokemon card Cornerstone Mask Ogerpon ex - 112/167 - SV06: Twilight Masquerade [C] Sob (20) duringyour opponents next turn Pokemon Card Game/[S4a] Shiny Star

The price estimates for these cards come from TCG Player's listing, and will likely change as the set releases and rarity is settled

A mythic rare printing of this ostensibly rare card just means the RVR printings (and their associated variants) will shoot up in price by the simple law of supply/demand

Pyroblast and Red Elemental Blast shut down everything from Thassa's Oracle to Rhystic Study, while Hydroblast and Blue Elemental Blast take out key red threats like Jeska's Will or Ragavan, Nimble Pilferer

If you overplay them assuming they are a generic answer you will come unstuck in various ways over your games