The black-green deck focuses primarily on +1/+1 counters. While most of the core pieces listed are uncommon, there are plenty of powerful commons that are useful to this deck as well. As you can probably see, there is a ton of overlap between the black-green and the green-white archetypes. Both of these decks often focus on creating a single large creature to end the game. As with all Draft formats, you will find overlap in cards; the key is to leverage the quality and synergy of color pairs such as black-green.