If you control a Vampire, each opponent loses 2 life and you gain 2 life
Like most Magic: The Gathering cards, the value of Plains depends on a few consistent factors: its rarity, the printing and finish (regular or foil), its physical condition, and the set it was printed in (The Brothers' War)
Fort Worth for example will follow the increased prizing, but since the Prize tickets were newly added as prizes, I am going to to assume they stay the same
Can You Have More Than One Full Party
(Must have a partner to play) The team does not share any other resources other than life
Were I looking at it from building a top 20 list, I would exclude this from consideration as the grading increase holds pretty level across the harder to find cards