Creature - Avatar 2/4, 6B (7) Flying Cumulative upkeep-Gain control of a land you don't control. Herald of Leshrac gets +1/+1 for each land you control but don't own. When Herald of Leshrac leaves play, each player gains control of each land he or she owns that you control.
Illus. Alex Horley-Orlandelli
You must choose different lands you don't control for each age counter. You cannot choose the same land more than once. [Coldsnap FAQ 2006/06/14]
The cumulative upkeep is put on the stack at the beginning of upkeep. If you remove this card from play before the cumulative upkeep resolves (by sacrificing it, for example), its "leaves play" ability will trigger and return any stolen lands. Then the cumulative upkeep will resolve. Since the card is no longer in play, you cannot add an age counter, but you can choose to pay the cost if you want based on the number of age counters it had when it left play. In this case, paying the cost involves stealing lands, which you get to keep. [D'Angelo 2006/08/18] See Rule 502.13.Ruling.5