Even top-heavy decks like those need creatures in the early game, Rivaz fits the bill
By giving the opponent a 1/1 Human token instead of a 3/3 Elephant, you significantly mitigate the risk of providing them with a meaningful attacker or blocker
Their deck of cards is their spellbook, with which creatures are summoned to battle each other and attack the opponent with
While they can be replaced by a Caterpie or Exeggcute and Exeggutor, its hard to beat Lilligants ability to add extra energy to a benched Pokmon
The set has incredible reprints, including Imperial Seal to Mana Vault and everything in between
The decks other character, Cruella De Vil, Miserable as Usual, is a much cheaper card able to be played earlier on, and can force characters off the field when shes banished by returning a character to its players hand - playing into the decks more control-like tendencies