The Pits of Hathsin

{t}: Add {c}.
Whenever you tap this land for mana,
create a Vial of Atium. Target creature
you control gets -1/-1 until end of turn.
Imprisoned skaa are required to climb down a suffocatingly narrow gorge and reach into crystal-lined niches to find the geodes that contain the atium. Each
Skaa has to find an atium geode every week; if they
fail, they are savagely beaten to death.