Flying

Cumulative upkeep—Gain control of a land you don't control. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)

Herald of Leshrac gets +1/+1 for each land you control but don't own.

When Herald of Leshrac leaves the battlefield, each player gains control of each land they own that you control.

Whenever an opponent casts a green spell, you may pay . If you do, look at that player's hand and choose a card from it. The player discards that card.

: Return Leshrac's Sigil to its owner's hand.