Portent Tracker

{T}: Untap target land.
{T}: Choose target battle. If an opponent protects it, remove a defense counter from it. Otherwise, put a defense counter on it. Activate only as a sorcery.

Loam Dryad

{T}, Tap an untapped creature you control: Add one mana of any color.

Overgrowth

Enchant land
Whenever enchanted land is tapped for mana, its controller adds an additional {G}{G}.

Blighted Burgeoning

Enchant land
When Blighted Burgeoning enters, incubate 2. (Create an Incubator token with two +1/+1 counters on it and "{2}: Transform this artifact." It transforms into a 0/0 Phyrexian artifact creature.)
Whenever enchanted land is tapped for mana, its controller adds an additional one mana of any color.

Ley Druid

Elvish Guidance

Enchant land
Whenever enchanted land is tapped for mana, its controller adds an additional {G} for each Elf on the battlefield.

Omnath, Locus of Mana

You don't lose unspent green mana as steps and phases end.
Omnath, Locus of Mana gets +1/+1 for each unspent green mana you have.

Juniper Order Druid

Urban Burgeoning

Enchant land
Enchanted land has "Untap this land during each other player's untap step."

Krosan Restorer

{T}: Untap target land.
Threshold — {T}: Untap up to three target lands. Activate only if seven or more cards are in your graveyard.

Glittering Frost

Enchant land
Enchanted land is snow.
Whenever enchanted land is tapped for mana, its controller adds an additional one mana of any color.

Sculptor of Winter

Curse of Bounty

Enchant player
Whenever enchanted player is attacked, untap all nonland permanents you control. Each opponent attacking that player untaps all nonland permanents they control.

Jaspera Sentinel

Reach
{T}, Tap an untapped creature you control: Add one mana of any color.

Llanowar Druid

{T}, Sacrifice Llanowar Druid: Untap all Forests.

Voyaging Satyr

Fertile Ground

Enchant land
Whenever enchanted land is tapped for mana, its controller adds an additional one mana of any color.

Saruli Caretaker

Defender
{T}, Tap an untapped creature you control: Add one mana of any color.

Rime Tender

{T}: Untap another target snow permanent.

Wolfwillow Haven

Enchant land
Whenever enchanted land is tapped for mana, its controller adds an additional {G}.
{4}{G}, Sacrifice Wolfwillow Haven: Create a 2/2 green Wolf creature token. Activate only during your turn.

Rustvine Cultivator

{T}: Put an oil counter on Rustvine Cultivator.
{T}, Remove an oil counter from Rustvine Cultivator: Untap target land.