It was six years before we saw the enemy pairs in Kaladesh
Given the power of the eternal card pool and the way color ID rules limit available answers, a preemptive lock card like Grafdiggers Cage, Null Rod or Trinisphere will often be your sole line of defense against well-tuned opposition
Flanking means "Whenever a creature without flanking blocks this creature, the blocking creature gets -1/-1 until end of turn." If a creature gains flanking during combat, that has no effect on any creature already blocking it
As a sorcery, you may pay the mana cost of a locked door to unlock it.) Illustrated by Cristi Balanescu Standard Legal Alchemy Legal Pioneer Legal Historic Legal Modern Legal Brawl Legal Legacy Legal Comp
You don't need a Squirtle and a Wartortle in order to send Radiant Blastoise onto the field, just as you don't need a Charmander or a Charmeleon for Charizard V
Keep in mind that pack points are accumulated separately by expansion, so open booster packs from Genetic Apex (A1) to get pack points for Charizard ex