Wasteland

{T}: Add {C}.
{T}, Sacrifice Wasteland: Destroy target nonbasic land.

Fellwar Stone

{T}: Add one mana of any color that a land an opponent controls could produce.

{T}: Add {C}.
{G}, {T}: Regenerate target creature.

Bojuka Bog enters tapped.
When Bojuka Bog enters, exile target player's graveyard.
{T}: Add {B}.

{T}: Add one mana of any color in your commander's color identity.

{T}: Add {C}.
{2}, {T}, Sacrifice a Desert: Exile all graveyards.