The choice of what the best cards in a format are is obviously always somewhat subjective, and it will come down to what a given player likes to play
Lightning Greaves is nice and all, but have you ever taken someones mana rock on turn 3
BPhillipYork: This could easily lead to you dumping out your whole deck if you've got a way to double counters, Doubling Season isn't in these colors but there are other ways
However you choose to partake in this epic set, as long as you are having fun and enjoying yourself, be safe in the knowledge that you are doing it right.
In this example we see that Grand Abolisher has a yellow/gold Expansion Symbol icon, this informs us that he is a Rare card
This card's price has seen some moderate fluctuation since its release, but overall, it has steadily increased in value over the last few months