'Pokemon Go' Eevee Evolutions: 2 Steps to Guarantee You'll Get a Sylveon! The secret evolution name for Sylveon will soon be available. Use these tips to automatically guarantee Eevee's next evolution in Pokemon Go! Photo : Tomohiro Ohsumi/Getty Images The secret evolution name for Sylveon will soon be available in 'Pokemon Go." Fortunately, there are ways to automatically guarantee Eevee's next evolution will be the Fairy-type Pokemon. Eevee is one of the most popular Pokemon with its iconic multi-evolution options. When Eevee has gained enough XP or Eevee Candies, trainers need to take critical steps to ensure the evolution to be the type they desire. A single mistake in the process could turn Eevee into one of the many other evolutions, including Vaporeon, Jolteon, Flareon, Espeon, Umbreon, Leafeon and Glaceon.