They are also cheap to find and available by the hundreds for your card stock
Lands produce magical energy, or mana, which is the fuel used to cast other spells
Of course, there are stories of this thing completely changing the game, but in general, there is usually enough enchantment removal floating around that most of the time this will probably do nothing (expect possibly draw out that enchantment removal, but you dont usually want to approach the game like that, especially in multiplayer)
On turn two, you can drop an Ichor Wellspring, then on three use Fanatical Offering to cash it in, and follow up with a one-mana Intervention
Those Boomerang Basics + Stormchaser's Talent loops or simply countering your opponents spells should give you an army