Sprite Animations
In the current era of fully rendered polygonal Pogeys, the longing for animations seems rather archaic. But imagine, if you will, seeing your beloved starting ally evolve into a mighty behemoth at long last, and only getting to appreciate that with one static image. They felt lifeless and cold, which perhaps made the fact that they were thrown into deadly combat a little easier to swallow. Then, along came Pokemon Crystal, and upon their summoning, your beasts would briefly wiggle. It was pure magic.
Obviously, with so many Pokemon smushed onto the meager memory of the Game Boy Color cartridge, they weren’t going to be very robust, and some were much better than others. But it added an element of vivification that made us associate with our party just that little bit more. Dragonite was a particular highlight, as its giddy boogie made it look like it had just received a piece of candy. We should all hope to someday be as delighted as that Dragonite.