Guardian Augmenter

Flash
Commander creatures you control get +2/+2.
Commanders you control have hexproof.

Bristly Bill, Spine Sower

Landfall — Whenever a land you control enters, put a +1/+1 counter on target creature.
{3}{G}{G}: Double the number of +1/+1 counters on each creature you control.

Spontaneous Flight

Target creature gets +2/+2 until end of turn. Put a flying counter on it.

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

Titanic Growth

Target creature gets +4/+4 until end of turn.

Crumb and Get It

Gift a Food (You may promise an opponent a gift as you cast this spell. If you do, they create a Food token before its other effects. It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")
Target creature you control gets +2/+2 until end of turn. If the gift was promised, that creature also gains indestructible until end of turn.

Bastion Protector

Commander creatures you control get +2/+2 and have indestructible.

Gyre Sage

Evolve (Whenever a creature you control enters, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.)
{T}: Add {G} for each +1/+1 counter on this creature.

Byrke, Long Ear of the Law

Vigilance
When Byrke enters, put a +1/+1 counter on each of up to two target creatures.
Whenever a creature you control with a +1/+1 counter on it attacks, double the number of +1/+1 counters on it.

Patchwork Banner

As this artifact enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.
{T}: Add one mana of any color.

Doubling Season

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.
If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

Branching Evolution

If one or more +1/+1 counters would be put on a creature you control, twice that many +1/+1 counters are put on that creature instead.

Blossoming Defense

Target creature you control gets +2/+2 and gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Birds of Paradise

Wild Growth

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

Arrester's Zeal

Target creature gets +2/+2 until end of turn.
Addendum — If you cast this spell during your main phase, that creature gains flying until end of turn.

Beaming Defiance

Hydra's Growth

Enchant creature
When this Aura enters, put a +1/+1 counter on enchanted creature.
At the beginning of your upkeep, double the number of +1/+1 counters on enchanted creature.

Wing It

Target creature gets +2/+2 until end of turn. Put a flying counter on it. Scry 1.

Herd Heirloom

{T}: Add one mana of any color. Spend this mana only to cast a creature spell.
{T}: Until end of turn, target creature you control with power 4 or greater gains trample and "Whenever this creature deals combat damage to a player, draw a card."

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Plains

Might of Old Krosa

Target creature gets +2/+2 until end of turn. If you cast this spell during your main phase, that creature gets +4/+4 until end of turn instead.

Seedcradle Witch

{2}{G}{W}: Target creature gets +3/+3 until end of turn. Untap that creature.

Sovereign Okinec Ahau

Ward {2}
Whenever Sovereign Okinec Ahau attacks, for each creature you control with power greater than that creature's base power, put a number of +1/+1 counters on that creature equal to the difference.

Magus of the Vineyard

At the beginning of each player's first main phase, that player adds {G}{G}.

Shalai, Voice of Plenty

Flying
You, planeswalkers you control, and other creatures you control have hexproof.
{4}{G}{G}: Put a +1/+1 counter on each creature you control.

Enlarge

Target creature gets +7/+7 and gains trample until end of turn. It must be blocked this turn if able. (A creature with trample can deal excess combat damage to the player or planeswalker it's attacking.)

Revelation of Power

Target creature gets +2/+2 until end of turn. If it has a counter on it, it also gains flying and lifelink until end of turn.

Avacyn's Pilgrim

Might of Oaks

Target creature gets +7/+7 until end of turn.

Shield of the Oversoul

Enchant creature
As long as enchanted creature is green, it gets +1/+1 and has indestructible. (Damage and effects that say "destroy" don't destroy it. If its toughness is 0 or less, it still dies.)
As long as enchanted creature is white, it gets +1/+1 and has flying.

Fanatic of Rhonas

{T}: Add {G}.
Ferocious — {T}: Add {G}{G}{G}{G}. Activate only if you control a creature with power 4 or greater.
Eternalize {2}{G}{G} ({2}{G}{G}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a 4/4 black Zombie Snake Druid with no mana cost. Eternalize only as a sorcery.)

Gerrard's Command

Untap target creature. It gets +3/+3 until end of turn.

Forest

Stonewood Invocation

Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
Target creature gets +5/+5 and gains shroud until end of turn. (It can't be the target of spells or abilities.)

Bloom Tender

Vivid — {T}: For each color among permanents you control, add one mana of that color.

Monstrous Growth

Sol Ring

Exponential Growth

Until end of turn, double target creature's power X times.

Overprotect

Target creature you control gets +3/+3 and gains trample, hexproof, and indestructible until end of turn.

Timely Ward

You may cast this spell as though it had flash if it targets a commander.
Enchant creature
Enchanted creature has indestructible.

Larger Than Life

Target creature gets +4/+4 and gains trample until end of turn.

Saryth, the Viper's Fang

Other tapped creatures you control have deathtouch.
Other untapped creatures you control have hexproof.
{1}, {T}: Untap another target creature or land you control.

Colossification

Enchant creature
When this Aura enters, tap enchanted creature.
Enchanted creature gets +20/+20.

Jump Scare

Until end of turn, target creature gets +2/+2, gains flying, and becomes a Horror enchantment creature in addition to its other types.