Forbidden Orchard

{T}: Add one mana of any color.
Whenever you tap Forbidden Orchard for mana, target opponent creates a 1/1 colorless Spirit creature token.

Intruder Alarm

Creatures don't untap during their controllers' untap steps.
Whenever a creature enters, untap all creatures.

Swamp

Yavimaya, Cradle of Growth

Each land is a Forest in addition to its other land types.

Voyaging Satyr

Sylvan Scrying

Search your library for a land card, reveal it, put it into your hand, then shuffle.

Blossom Dryad

Llanowar Loamspeaker

{T}: Add one mana of any color.
{T}: Target land you control becomes a 3/3 Elemental creature with haste until end of turn. It's still a land. Activate only as a sorcery.

Banefire

Banefire deals X damage to any target.
If X is 5 or more, this spell can't be countered and the damage can't be prevented.

Arbor Elf

Mountain

Rampaging Ferocidon

Menace
Players can't gain life.
Whenever another creature enters, Rampaging Ferocidon deals 1 damage to that creature's controller.

Forest

Freed from the Real

Enchant creature
{U}: Tap enchanted creature.
{U}: Untap enchanted creature.

Trespasser's Curse

Enchant player
Whenever a creature enchanted player controls enters, that player loses 1 life and you gain 1 life.