With each evolution, the Pokemon becomes stronger and learns new skills, and you can play both the basic and evolution cards in a Pokemon battle
How about 2 of each
It especially benefits from Cromat's ability that returns it to the top of the deck, since when mutated all cards are considered one, making you not lose value, leaving your resources safe with the ability to return everyone to your deck in front of a removal With access to five colors it is easy to choose the best from the list of creatures with this ability, such as Nethroi, Apex of Death and make your Cromat invincible
This topic is worthy of an article in itself, but I'll give a condensed lesson on the topic here since it's important to know about when building a Jodah, Archmage Eternal deck
[9] The classic example is Krenko, Mob Boss
Fervent Champion on T1, and Sword of the Animist or Mask of Memory on T2