Dimir Aqueduct enters the battlefield tapped. When Dimir Aqueduct enters the battlefield, return a land you control to its owner's hand. {T}: Add {U}{B}.
Golgari Rot Farm enters the battlefield tapped. When Golgari Rot Farm enters the battlefield, return a land you control to its owner's hand. {T}: Add {B}{G}.
Selesnya Sanctuary enters the battlefield tapped. When Selesnya Sanctuary enters the battlefield, return a land you control to its owner's hand. {T}: Add {G}{W}.
{T}: Add {C}. {3}{B}{G}: Until end of turn, Svogthos, the Restless Tomb becomes a black and green Plant Zombie creature with "This creature's power and toughness are each equal to the number of creature cards in your graveyard." It's still a land.