By and large, three and six drops are better and more impactful
You can combine these effects with Anafenza, the Foremost, Leyline of the Void or Liesa, Forgotten Archangel to make it so opponents creatures never come back again
As the name suggests, this format was popularized alongside the Planechase MTG set
For a collector looking to pick up a number of LOTR MTG cards for the first time, grabbing a binder to display your new cardboard pieces in, or a playmat to use on your desk at home may be more appropriate
Right now, it's really hard to figure out who actually buys Masters sets from big-box stores
Once Pack Leader attacks, its effect prevents damage that would be dealt to Dogs you control even if Pack Leader leaves the battlefield