When you mouse over a flip, transform or Morph (controlled by you) card in battlefield, hold SHIFT to see other state of that card at the side panel that displays card picture and details
The Donald Duck Enchanted card from Shimmering Skies is currently selling for an average price of $100 , with its standard, Legendary variant selling for less than $5
PPC - Psychic Willpower 110 Krabby W - Fiddle Flip a coin
However, you could take the list as most iconic from each era too for example, tapu lele GX definitely signifies SM era standard format
The Mystical Archive is a reprint collection of the most iconic instant and sorcery spells from throughout Magic's history which was first introduced in Strixhaven: School of Mages in 2021
Be cautious, as many listed as 1st Edition are actually the Unlimited version