One Pokemon fan has pointed out that only the Generation 1 Eevee evolutions have a mane. Eevee had three potential evolutions in the original Pokemon games. Using evolution stones, players could evolve their Eevee into Electric-type Jolteon, Fire-type Flareon, or Water-type Vaporeon. However, future Pokemon generations added more Eevee evolutions to the mix.
The Generation 2 Pokemon games added the popular Psychic-type Espeon and Dark-type Umbreon Eevee evolutions, while Generation 4 introduced Grass-type Leafeon and Ice-type Glaceon. Fairy-type Sylveon is the latest Eevee evolution, added as part of the Generation 6 games Pokemon X and Y. While many Pokemon fans have wanted to see more Eevee evolutions that represent the other Pokemon types, no new Eevee evolutions were added in Generations 7, 8, or 9.
The persistent popularity of Eevee and its evolutions makes its surprising that Pokemon hasn't added more to the mix. Regardless, Pokemon fans continue to notice new details about the Eevee evolutions, with Reddit user sBroz410 pointing out that the Generation 1 Eevee evolutions are the only ones where Eevee keeps its mane after evolving. Eevee's mane disappears with all the other Eevee evolutions, unless one counts Sylveon's bow standing in as the mane.
It's unclear why this design decision was made, but it is an interesting way that the Generation 1 Eevee evolutions stand out from the rest. If new Eevee evolutions are ever introduced to the Pokemon franchise, it will be interesting to see if they retain the mane or go without. With the Generation 10 Pokemon games likely still years away at this point, fans will have to wait a bit before learning about what the next Eevee evolutions have in store.
With Game Freak, Nintendo, and The Pokemon Company skipping on new Eevee evolutions for the last few generations, fans have taken matters into their own hands. Pokemon fans have designed all kinds of new Eevee evolutions, with Ghost-type Eevee forms being especially popular in fan art.
While some fans want to see more Eevee evolutions in Pokemon, others have different ideas. Reddit user ---TheFierceDiety--- proposed the idea of a rival Eevee Pokemon that would have Eevee's gimmick of evolving into different Pokemon of varying types, but with this Pokemon embodying the types that have yet to be represented with Eevee evolutions. Nine of the 18 Pokemon types are already represented by Eevee, so the hypothetical rival Eevee could have an even number of forms. The idea generated quite a bit of excitement from the Pokemon community, but it remains to be seen if the developers will ever pursue something like it.
