Theros had an enchantment theme (which could have been more prominent and powerful, but thats a different article) and it also had the Heroic keyword, which triggered when you cast a spell targeting a creature
Offers multiple card slots to organize and display your Fabled, Common, and Rare cards
Being instant speed also makes it incredibly flexible, allowing you to hold countermagic or cast this if nothing needs to be countered
If you cant, you may find your value comes a little too late when compared to your opponents who could have devastating board states by the time youre ready
As such, while well explore alternate combinations of Doctor and Companion, well stick to the overall color identity of White-Blue-Green
Chronomantic Escape also reexiles itself upon resolution, letting you cast it from exile again next turn