How about Gaseon (poison-type eeveelution) or Thundereon (electric type. I know there's Jolteon, but still...)? Or maybe Steeleon (steel type, obviously) Rockeon (rock type), or Psycheon (psychic type). I'm literally just coming up with all these right now. Ooh, what about Lighteon or Cosmeon (light or cosmic type. Those are some popular fanmade Pokémon types)?