Umbreon, The moonlight Pokemon, and one of the evolved forms of Eevee. When darkness falls, the rings on the body begin to glow, striking fear in the hearts of anyone nearby. Umbreon evolves from Eevee with high happiness during the night.
Day: 12:00 - 23:59
Night: 00:00 - 11:59
"/time" or "/servertime" will give display the ingame time. This is also indicated by the clock in the UI.
In PokeMMO, 512 steps raises Pokemon happiness by one. This is double (256) than the hard copy, solo game requirements. (Needs confirmation). Using the bicycle does count as taking steps.
Battling, and winning or fainting, will also raise or lower your Pokemon's happiness. (This may not be implemented as of 5/8/2013).
Umbreon has been known to evolve with a happiness of 87% or higher (needs confirmation). After passing this threshhold, leveling the pokemon up via battling or Rare Candy will trigger the evolution from Eevee.