Budget casual legacy. Built to maximize fun. May or may not be fun for your opponents because you will be destroying their lands. Following is an explanation for each card except for Terravore because that should be self-evident.
Fuel the Terravore using land destruction:
Bust
Raze
Stone Rain
Devastating Dreams,
and land sacrifice/discard:
Harrow
Edge of Autumn
Forgotten Cave, Tranquil Thicket
Sandstone Needle, Hickory Woodlot
Barbarian Ring.
Protect your Terravore investment (1GG don't come easy after all!) by shrouding it using Lightning Greaves (Bonus: Haste), and by destroying the enemy's creatures:
Barbarian Ring
Devastating Dreams.
Note: Devastating Dreams will almost never kill your Terravore due to the fact that state-based actions such as checking for dead things will occur after the spell resolves!
Ramp up your mana using:
Wall of Roots
Harrow
Sandstone Needle, Hickory Woodlot
Werebear
Edge of Autumn.
Tutor for your Terravore using Fauna Shaman (damn, that is some nice fauna)!
Last, but not least, ensure a swift start using these classics:
Mountain
Forest.
As for the sideboard, you've got your nonbasic-land-hate:
Detritivore (he's not great but what the hell)
Molten Rain,
Lodestone Bauble for controlling your enemy's card draw (yes, it weakens the Terravore, but it also prevents your opponent from doing anything about the Terravore when you have battlefield control, such as after casting Devastating Dreams, also it's hilarious), Tempting Wurm against control decks that will primarily put out lands that you will then destroy, and another Devastating Dreams in case you're up against swarms of little things.
