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.)

Grazing Whiptail

Ancient Imperiosaur

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
Trample, ward {2}
Ancient Imperiosaur enters with two +1/+1 counters on it for each creature that convoked it.

Aerial Volley

Aerial Volley deals 3 damage divided as you choose among one, two, or three target creatures with flying.

Ancient Brontodon

Access Tunnel

{T}: Add {C}.
{3}, {T}: Target creature with power 3 or less can't be blocked this turn.

Aerial Predation

Destroy target creature with flying. You gain 2 life.

Azorius Chancery

Azorius Chancery enters tapped.
When Azorius Chancery enters, return a land you control to its owner's hand.
{T}: Add {W}{U}.

Curious Altisaur

Vigilance, reach
Whenever a Dinosaur you control deals combat damage to a player, draw a card.

Cresting Mosasaurus

Emerge {6}{U} (You may cast this spell by sacrificing a creature and paying the emerge cost reduced by that creature's mana value.)
When Cresting Mosasaurus enters, if you cast it, return each non-Dinosaur creature to its owner's hand.

Acrobatic Leap

Target creature gets +1/+3 and gains flying until end of turn. Untap it.

Abandoned Outpost

Abandoned Outpost enters tapped.
{T}: Add {W}.
{T}, Sacrifice Abandoned Outpost: Add one mana of any color.

Carnivorous Death-Parrot

Flying
At the beginning of your upkeep, sacrifice Carnivorous Death-Parrot unless you say its flavor text.

Birds of Paradise

Absorb

Warden of Evos Isle

Flying
Creature spells with flying you cast cost {1} less to cast.

Arctic Aven

Flying
Arctic Aven gets +1/+1 as long as you control a Plains.
{W}: Arctic Aven gains lifelink until end of turn. (Damage dealt by this creature also causes you to gain that much life.)

Forest

Aerial Maneuver

Target creature gets +1/+1 and gains flying and first strike until end of turn.

Island

Bay Falcon

Annoyed Altisaur

Reach, trample
Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Nadu, Winged Wisdom

Flying
Creatures you control have "Whenever this creature becomes the target of a spell or ability, reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put it into your hand. This ability triggers only twice each turn."

Abolish

You may discard a Plains card rather than pay this spell's mana cost.
Destroy target artifact or enchantment.

Winged Words

This spell costs {1} less to cast if you control a creature with flying.
Draw two cards.

Adarkar Wastes

{T}: Add {C}.
{T}: Add {W} or {U}. Adarkar Wastes deals 1 damage to you.

Act of Heroism

Untap target creature. It gets +2/+2 until end of turn and can block an additional creature this turn.

Abbey Griffin

Plains

Armored Kincaller

When Armored Kincaller enters, you may reveal a Dinosaur card from your hand. If you do or if you control another Dinosaur, you gain 3 life.

Boreal Shelf

Boreal Shelf enters tapped.
{T}: Add {W} or {U}.

Augury Owl

Flying
When Augury Owl enters, scry 3. (Look at the top three cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Cherished Hatchling

When Cherished Hatchling dies, you may cast Dinosaur spells this turn as though they had flash, and whenever you cast a Dinosaur spell this turn, it gains "When this creature enters, you may have it fight another target creature."

Aerial Assault

Destroy target tapped creature. You gain 1 life for each creature you control with flying.

Sol Ring

Aven Smokeweaver

Talrand, Sky Summoner

Whenever you cast an instant or sorcery spell, create a 2/2 blue Drake creature token with flying.

Derevi, Empyrial Tactician

Flying
When Derevi, Empyrial Tactician enters and whenever a creature you control deals combat damage to a player, you may tap or untap target permanent.
{1}{G}{W}{U}: Put Derevi onto the battlefield from the command zone.