Rampant Growth

Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Pollenbright Druid

When Pollenbright Druid enters the battlefield, choose one —
• Put a +1/+1 counter on target creature.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Pridemalkin

When Pridemalkin enters the battlefield, put a +1/+1 counter on target creature you control.
Each creature you control with a +1/+1 counter on it has trample. (They can deal excess combat damage to the player or planeswalker they're attacking.)

Ranger's Guile

Target creature you control gets +1/+1 and gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Kodama's Reach

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Llanowar Elves

Fertilid

Fertilid enters the battlefield with two +1/+1 counters on it.
{1}{G}, Remove a +1/+1 counter from Fertilid: Target player searches their library for a basic land card, puts it onto the battlefield tapped, then shuffles.

Tuskguard Captain

Outlast {G} ({G}, {T}: Put a +1/+1 counter on this creature. Outlast only as a sorcery.)
Each creature you control with a +1/+1 counter on it has trample.

Ivy Lane Denizen

Whenever another green creature enters the battlefield under your control, put a +1/+1 counter on target creature.

Servant of the Scale

Servant of the Scale enters the battlefield with a +1/+1 counter on it.
When Servant of the Scale dies, put X +1/+1 counters on target creature you control, where X is the number of +1/+1 counters on Servant of the Scale.

Chronicler of Heroes

When Chronicler of Heroes enters the battlefield, draw a card if you control a creature with a +1/+1 counter on it.

Qasali Pridemage

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
{1}, Sacrifice Qasali Pridemage: Destroy target artifact or enchantment.

Arcane Signet

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

Spirited Companion

When Spirited Companion enters the battlefield, draw a card.

Star Pupil

Star Pupil enters the battlefield with a +1/+1 counter on it.
When Star Pupil dies, put its counters on target creature you control.

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's still put into its owner's graveyard.)
As long as enchanted creature is white, it gets +1/+1 and has flying.

Elvish Mystic

Elvish Visionary

When Elvish Visionary enters the battlefield, draw a card.

Rancor

Enchant creature
Enchanted creature gets +2/+0 and has trample.
When Rancor is put into a graveyard from the battlefield, return Rancor to its owner's hand.

Armadillo Cloak

Enchant creature
Enchanted creature gets +2/+2 and has trample.
Whenever enchanted creature deals damage, you gain that much life.

Mirri, Weatherlight Duelist

First strike
Whenever Mirri, Weatherlight Duelist attacks, each opponent can't block with more than one creature this combat.
As long as Mirri, Weatherlight Duelist is tapped, no more than one creature can attack you each combat.

Plains

Avacyn's Pilgrim

Snake Umbra

Enchant creature
Enchanted creature gets +1/+1 and has "Whenever this creature deals damage to an opponent, you may draw a card."
Totem armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Forest

Gaea's Gift

Put a +1/+1 counter on target creature you control. It gains reach, trample, hexproof, and indestructible until end of turn. (It can't be the target of spells or abilities your opponents control. Damage and effects that say "destroy" don't destroy it.)

Snakeskin Veil

Put a +1/+1 counter on target creature you control. It gains hexproof until end of turn. (It can't be the target of spells or abilities your opponents control.)

Thraben Inspector

When Thraben Inspector enters the battlefield, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this artifact: Draw a card.")

Cultivate

Ethereal Armor

Enchant creature
Enchanted creature gets +1/+1 for each enchantment you control and has first strike.

Master Chef

Commander creatures you own have "This creature enters the battlefield with an additional +1/+1 counter on it" and "Other creatures you control enter the battlefield with an additional +1/+1 counter on them."

Angelic Gift

Enchant creature
When Angelic Gift enters the battlefield, draw a card.
Enchanted creature has flying.