When a card or archetype becomes dominant, the metagame will change relatively slowly, and it may take a ban or an impactful set to shake things up
These tournament promos can be worth hundreds of dollars, or more
Yu-Gi-Oh Known for deep combo lines, big turns, and a higher complexity ceiling thanks to long card texts and advanced mechanics
Even those that have real cards on the back dont tend to have big mana value differences between them, so the benefit for transforming isnt massive
9 Pikachu Speaking of the franchises iconic mascot, Pikachu was a far more common card, but, like Charizard, it had some of the best art in the Base Set (no surprise given that Mitsuhiro Arita was behind the art for both)
A cunning opponent might try and bait out your spell so that they can play a more threatening card later on