Here is how I run this in real life: When a creature arrives to the battlefield, we flip over equipment until one flips over that meets the requirement
1.111 per cent chance: 0.222 per cent per card (5th card probability rate, regular pack) Full Art Arcanine EX, Full Art Blastoise EX, Full Art Pikachu EX, Full Art Zapdos EX, Full Art Wigglytuff EX (Pikachu Pack) 0.25 per cent chance: 0.05 per cent per card (4th card, regular pack)
Gisela and Bruna end up as the distinctly less angelic Brisela: Unfortunately, theres only a few meld cards in the setthree pairs of two eachbut thankfully, one of the pairs is at the common rarity, so youll be able to easily get hold of it and try out the mechanic for yourself
Then there are Walls that are just hard to crack, like Glacial Wall and Wall of Ice
This makes it a niche but super fun pick for spirit tribal or Kamigawa-style decks that use cheap, efficient arcane spells