Flying (This creature can't be blocked except by creatures with flying or reach.)

As long as Gaea's Liege isn't attacking, its power and toughness are each equal to the number of Forests you control. As long as Gaea's Liege is attacking, its power and toughness are each equal to the number of Forests defending player controls.
: Target land becomes a Forest until this creature leaves the battlefield.

Flying
: This creature gets +1/+0 until end of turn.

This creature enters with seven +1/+0 counters on it.
At end of combat, if this creature attacked or blocked this combat, remove a +1/+0 counter from it.
, : Put up to X +1/+0 counters on this creature. This ability can't cause the total number of +1/+0 counters on this creature to be greater than seven. Activate only during your upkeep.

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
At the beginning of your upkeep, this creature deals 8 damage to you unless you pay .

: Destroy target land.
At the beginning of your upkeep, unless you pay , tap this creature and sacrifice a land of an opponent's choice.

: The next 1 damage that would be dealt to this creature this turn is dealt to its owner instead. Only this creatures owner may activate this ability.
When this creature dies, its owner loses half their life, rounded up.

Flying (This creature can't be blocked except by creatures with flying or reach.)
Nightmare's power and toughness are each equal to the number of Swamps you control.

Flying, trample
At the beginning of your upkeep, sacrifice a creature other than this creature. If you can't, this creature deals 7 damage to you.