Originally Posted by
sdematt
To do average cost, you can find out how many you have total (total spells), and see how many you have of each, and see what percentage.
Example, you have 3/15 spells that cost 2, 2/15 3-drops, and 10/15 1 drops, you need some percentages.
2 Drops: 20% of total (.20)
1 drops: 66% of toal (.66)
3 drops: 14% of total (.14)
(2x2) + (2x3) + (10x1)= some number
(some number)/15 = average CMC. You're basically adding up the total casting cost of every card, then dividing by the total number of cards to get the average. The percentages are there to show how top or bottom heavy your deck is. Also, I thought I needed them for something else, but apparently, I didn't.
In Rock, if your curve is ~2 (1.8-2.2) I tend to find 19 mana producers + utility lands enough. If you're curving closer to 3, 22 Mana producers are your safe bet. You also have to expect getting Wastelanded twice, conservatively.
-Matt