Forest

Frogmite

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)

Mishra's Bauble

{T}, Sacrifice Mishra's Bauble: Look at the top card of target player's library. Draw a card at the beginning of the next turn's upkeep.

Wooded Foothills

{T}, Pay 1 life, Sacrifice Wooded Foothills: Search your library for a Mountain or Forest card, put it onto the battlefield, then shuffle.

Paradise Mantle

Equipped creature has "{T}: Add one mana of any color."
Equip {1}

Ornithopter

Dryad Arbor

(Dryad Arbor isn't a spell, it's affected by summoning sickness, and it has "{T}: Add {G}.")

Burning-Tree Emissary

When Burning-Tree Emissary enters, add {R}{G}.

Memnite

Manamorphose

Add two mana in any combination of colors.
Draw a card.

Ghalta, Primal Hunger

This spell costs {X} less to cast, where X is the total power of creatures you control.
Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)

Thrasta, Tempest's Roar

This spell costs {3} less to cast for each other spell cast this turn.
Trample, haste
Trample over planeswalkers (This creature can deal excess combat damage to the controller of the planeswalker it's attacking.)
Thrasta, Tempest's Roar has hexproof as long as it entered this turn.

Hidden Herbalists

Revolt — When Hidden Herbalists enters, if a permanent you controlled left the battlefield this turn, add {G}{G}.