Eevee can evolve into eight different forms, each with its own unique type and abilities. These evolutions are: Vaporeon (Water), Jolteon (Electric), Flareon (Fire), Espeon (Psychic), Umbreon (Dark), Leafeon (Grass), Glaceon (Ice), and Sylveon (Fairy). The type of stone or method used to evolve Eevee determines which form it will take. Each evolution has its own strengths and weaknesses, making Eevee a versatile and valuable Pokémon to have in battle.