+obsidian (6)
Protection from black
: Target creature gains protection from black until end of turn.
Equipped creature gets +2/+1 and has haste.
Whenever a Warrior creature enters the battlefield, you may attach Obsidian Battle-Axe to it.
Equip
This spell costs less to cast for each land your opponents control that could produce .
Flying
When Obsidian Charmaw enters the battlefield, destroy target nonbasic land an opponent controls.
: Put a blaze counter on target land without a blaze counter on it. For as long as that land has a blaze counter on it, it has "At the beginning of your upkeep, this land deals 1 damage to you." (The land continues to burn after Obsidian Fireheart has left the battlefield.)
Obsidian Obelisk enters the battlefield tapped.
: Add .
: Add one mana of any color. Spend this mana only to cast a multicolored spell.
Gatherer works better in the Companion app!
less to cast for each land your opponents control that could produce 
.