You can only use this effect of "Undaunted Bumpkin Beast" once per turn
This is because there's another Booster Fun version of Okoa borderless versionand in general, our heuristic is to maintain the relative ratios of "Booster Fun versions of Oko" with "Booster Fun versions of other mythic rares." This means that if a card has multiple Booster Fun treatments, you're less likely to open any particular version, but you're just as likely to open a Booster Fun version of Oko as any other card overall
Ishiz's study was aided by the Millennium Item she wore The Millennium Necklace
However, since "Subterror Behemoth Stygokraken" is superior in the essential effect, there is no reason to choose this one
Not every card is a heavy hitter, and some fall by the wayside while others become meta-defining staples that see play for months or even years to come
His main job is to create his own GY for missionaries, throwing away high-ranking, etc., and it can also be used as a synchro material such as arkanite for Spellcaster