I had two ideas for it, first was to mix all sets with all generations but the second idea I had was to only use gen 4 released sets for the gen 4 Pokmon and do this for all the gens
#7 Given that you can summon a Blue-Eyes, Ultimate Dragon by special summoning it when you sacrifice 4x BEWDs, I feel like they should NOT be legendary, as you'll need multiple on the field at a time
So knowing this about the first two Pokemon in this line and looking at this specific Porygon-Z, the main reason you would want to use this card in a deck is for its Digital Reboot move, the reason you would want to use this move so often is to be able to reuse an Ability from let's say a Stage 2 Pokemon every single turn, like Aggron from Dragons Exalted (if you're playing in the expanded format) where you can use its Toppling Wind Ability to discard the top 3 cards of your opponent's deck every single turn and hopefully be able to win the game that way
Deggers adds, Its predatory
Features artwork of Karlach, Fury of Avernus by Billy Christian