Simultaneously has some of the coolest, most unique gameplay mechanics in the series, as well as some of the most outdated, annoying, and dusty-ass design choices in the series.

It's also hard to overstate how good FE4's story and atmosphere are compared to the rest of the series. There's real emotion there, with an overarching story about love, betrayal, and friendships that manage to span generations against all odds. It's the only time Fire Emblem has ever really had a worthwhile story beyond "Evil nation invades, then local blue-haired guy and his friends have to go kill a dragon."