This rare Darkness Energy was one of the first player rewards printed by Nintendo during this new era
Mentor of the Meek [c]Mentor of the Meek[/c] fits very well in a white deck playing lots of small creatures
When you add in time for rolling and wacky effects, Planechase Commander games can take a while, too, so you should probably expect to settle in for a little longer than normal, though some of the new planes really encourage attacking and moving the game along, so maybe less than you might think if you're used to Planechase Commander already
Probably try and avoid playing too much like this, just enough to keep you able to spend your mana each turn and have relevant stuff to do in the early turns
Ultimately, players will have to playtest the cards themselves to see if Galadriel can keep up with today's power levels in Modern and Commander, but it doesn't look likely
Because of this, I have found trading your unopened booster packs to be THE BEST way to get all of the cards that you need