When this creature enters, mill three cards. You may put a land card from among the cards milled this way into your hand. If you don't, put a +1/+1 counter on this creature. (To mill a card, put the top card of your library into your graveyard.)

Whenever this creature enters or attacks, mill three cards, then return a land card from your graveyard to the battlefield tapped. Activated abilities of lands you control cost {1} less to activate. Land creatures you control get +1/+1.

This spell costs {1} less to cast for each Cave you control and each Cave card in your graveyard. Lifelink

When this creature enters, look at the top X cards of your library, where X is the number of Caves you control plus the number of Cave cards in your graveyard. Put two of those cards into your hand and the rest on the bottom of your library in a random order.

When this enchantment enters, create a 1/1 black Bat creature token with flying for each mana from a Cave spent to cast it. Whenever a Cave you control enters, put a +1/+1 counter on target creature you control.

This land enters tapped unless you control a legendary green creature. {T}: Add {G}. {2}{G}{G}, {T}: Create a 2/2 green Bear creature token, then mill three cards. Activate only as a sorcery. (Melds with Titania, Voice of Gaea.)

{T}: Add {C}. {2}: This land becomes a 3/3 Elemental creature until end of turn. It's still a Cave land. Activate only if the number of other Caves you control plus the number of Cave cards in your graveyard is three or greater.

({T}: Add {G}.)

{T}: Add {C}. Other Caves you control have "{T}, Pay 1 life: Add one mana of any color."

This land enters tapped. {T}: Add {U}. {4}{U}, {T}, Sacrifice this land: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

This land enters tapped. {T}: Add {W}. {4}{W}, {T}, Sacrifice this land: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

This land enters tapped. {T}: Add {B}. {4}{B}, {T}, Sacrifice this land: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

This land enters tapped. {T}: Add {G}. {4}{G}, {T}, Sacrifice this land: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

This land enters tapped. {T}: Add {R}. {4}{R}, {T}, Sacrifice this land: Discover 4. Activate only as a sorcery. (Exile cards from the top of your library until you exile a nonland card with mana value 4 or less. Cast it without paying its mana cost or put it into your hand. Put the rest on the bottom in a random order.)

Calamitous Cave-In deals X damage to each creature and each planeswalker, where X is the number of Caves you control plus the number of Cave cards in your graveyard.

Choose three. You may choose the same mode more than once. • Search your library for a Cave card, put it onto the battlefield tapped, then shuffle. • Put three +1/+1 counters on a Cave you control. It becomes a 0/0 Elemental creature with haste. It's still a land. • Destroy target enchantment.