Amber and Amethyst likes to quest early and often. Emerald and Ruby is especially good at delaying your opponents progress early on. Sapphire and Steel is great at quickly increasing the amount of ink in your inkwell. Those descriptions from the quick-start rules for each deck proved true
These are not necessarily stronger than other rarities (although they can be) when it comes to the card game, but they are harder to come by when opening packs
Let any human settlement grow too large, or advance too far, and suddenly you have Sin knocking at its doorstep, ready to annihilate everyone, spitting out a corrupted husk afterwards
Mufasa acts as a massive late-game play that lets players check the top 5 cards of their deck and play characters for free whenever he quests or is challenged
And while Magic has featured other video game crossovers in the past (hello, Assassins Creed and Fallout !), with the way this set is constructed, from card mechanics to art, you can tell this one is a developer favorite, sure to appeal to the massive chunk of people who love both games
And, it's true, they do synergize very well with their overlord