The pokemon charizard card wasnt elevated later by marketing or rarity engineering it set the standard from day one
(Every set, we ask Magic -playing employees to give us their first impressions of the cards.) The development team decided to take the best one (the green one), make it bigger, give it trample to help it get through, and then scrap the other four
In fact, there was a small sprinkling of one or two in these sets, except for Doctor Who, which gave us six
In the anime, when a Duelist uses Pendulum Summoning to gather the materials required for a Fusion, Synchro, or Xyz Summon, it is referred to as performing a "Pendulum-Fusion", "Pendulum-Synchro", or "Pendulum-Xyz Summon", respectively
One thing to be aware of is that you may pull some Commander-only cards out of Collector Booster packs, so you'll want to check the set symbols before building Standard decks