It tends to value highly in any set it appears in, but none are as rare as EX Deoxys' Rayquaza Gold Star, which only has 56 verified PSA 10 quality cards in circulation, putting it on par with the famous Holo Base Set Shadowless Charizard
Abilities that trigger "when [that creature] connives" will trigger.
To finish off, you can grab Beseech the Mirror and sacrifice a token to it to tutor up Tendrils of Agony, doming your opponent for the win
While Trading PostTrading Post acted as more of an engine for Brudiclad, Telchor EngineerBrudiclad, Telchor Engineer by making Goats, and the sacrificing ability was more of a backup, for Oviya, the opposite is true, and the recursion and card draw are much more impactful
Consider graded copies for authentication and protection
Upheaval into just a bunch of mana production, perhaps a card draw planeswalker too is so utterly game over and that set of stuff is without an actual threat