ST01-014-guard-point and OP01-029-radical-beam are excellent counter events, that also happen to be Straw Hat cards
Its an excellent board wipe, and its lethality is hard to argue with
I expect Nyxbloom Ancient to see a lot of play, and I'm already tired of it just from watching the THB preview streams, but I think it's fine staying legal in the format
Ruby cards offer players a more aggressive style of play while the Sapphire cards add support and a balance to the aggression of the Ruby cards
For more price spike stories, check out the Izzet Lord of the Rings card that's making a splash in Modern, and the run of interest in BG3's Karlach card
As mentioned, MTG Arena does offer in-game purchases of digital currency, which can then be spent on packs of cards