Kyler, Sigardian Emissary

Whenever another Human you control enters, put a +1/+1 counter on Kyler.
Other Humans you control get +1/+1 for each counter on Kyler.

Farmer Cotton

When this creature enters, create X 1/1 white Halfling creature tokens and X Food tokens. (They're artifacts with "{2}, {T}, Sacrifice this token: You gain 3 life.")

Plains

Mentor of the Meek

Whenever another creature you control with power 2 or less enters, you may pay {1}. If you do, draw a card.

Gala Greeters

Alliance — Whenever another creature you control enters, choose one that hasn't been chosen this turn —
• Put a +1/+1 counter on this creature.
• Create a tapped Treasure token.
• You gain 2 life.

Avacyn's Pilgrim

Command Tower

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

Wyrm's Crossing Patrol

Myriad (Whenever this creature attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

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.

Hardened Scales

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

Forest

Managorger Hydra

Trample
Whenever a player casts a spell, put a +1/+1 counter on this creature.

Rosie Cotton of South Lane

When Rosie Cotton enters, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")
Whenever you create a token, put a +1/+1 counter on target creature you control other than Rosie Cotton.

Bess, Soul Nourisher

Whenever one or more other creatures you control with base power and toughness 1/1 enter, put a +1/+1 counter on Bess.
Whenever Bess attacks, each other creature you control with base power and toughness 1/1 gets +X/+X until end of turn, where X is the number of +1/+1 counters on Bess.

Queen Allenal of Ruadach

Queen Allenal of Ruadach's power and toughness are each equal to the number of creatures you control.
If one or more creature tokens would be created under your control, those tokens plus a 1/1 white Soldier creature token are created instead.

Cadira, Caller of the Small

Trample
Whenever Cadira deals combat damage to a player, for each token you control, create a 1/1 white Rabbit creature token.

Haazda Marshal

Whenever this creature and at least two other creatures attack, create a 1/1 white Soldier creature token with lifelink.

Sigil Captain

Whenever a creature you control enters, if that creature is 1/1, put two +1/+1 counters on it.

King Darien XLVIII

Other creatures you control get +1/+1.
{3}{G}{W}: Put a +1/+1 counter on King Darien and create a 1/1 white Soldier creature token.
Sacrifice King Darien: Creature tokens you control gain hexproof and indestructible until end of turn.

Canopy Vista

({T}: Add {G} or {W}.)
This land enters tapped unless you control two or more basic lands.

Katilda, Dawnhart Prime

Protection from Werewolves
Human creatures you control have "{T}: Add one mana of any of this creature's colors."
{4}{G}{W}, {T}: Put a +1/+1 counter on each creature you control.

Keleth, Sunmane Familiar

Whenever a commander you control attacks, put a +1/+1 counter on it.
Partner (You can have two commanders if both have partner.)

Brigid, Doun's Mind

{T}: Add X {G} or X {W}, where X is the number of other creatures you control.
At the beginning of your first main phase, you may pay {W}. If you do, transform Brigid.

Brigid, Clachan's Heart

Whenever this creature enters or transforms into Brigid, Clachan's Heart, create a 1/1 green and white Kithkin creature token.
At the beginning of your first main phase, you may pay {G}. If you do, transform Brigid.

Brigid, Clachan's Heart // Brigid, Doun's Mind

Path of Ancestry

This land enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Fyndhorn Elves

Oketra's Monument

White creature spells you cast cost {1} less to cast.
Whenever you cast a creature spell, create a 1/1 white Warrior creature token with vigilance.

Elvish Mystic

Rabble Rousing

Hideaway 5 (When this enchantment enters, look at the top five cards of your library, exile one face down, then put the rest on the bottom in a random order.)
Whenever you attack with one or more creatures, create that many 1/1 green and white Citizen creature tokens. Then if you control ten or more creatures, you may play the exiled card without paying its mana cost.

Torens, Fist of the Angels

Training (Whenever this creature attacks with another creature with greater power, put a +1/+1 counter on this creature.)
Whenever you cast a creature spell, create a 1/1 green and white Human Soldier creature token with training.

Llanowar Elves

Scepter of Celebration

Equipped creature gets +2/+0 and has trample.
Whenever equipped creature deals combat damage to a player, create that many 1/1 green and white Citizen creature tokens.
Equip {3}

Champion of Lambholt

Creatures with power less than this creature's power can't block creatures you control.
Whenever another creature you control enters, put a +1/+1 counter on this creature.

Maja, Bretagard Protector

Other creatures you control get +1/+1.
Landfall — Whenever a land you control enters, create a 1/1 white Human Warrior creature token.

Intangible Virtue

Creature tokens you control get +1/+1 and have vigilance.

Silk, Web Weaver

Web-slinging {1}{G}{W} (You may cast this spell for {1}{G}{W} if you also return a tapped creature you control to its owner's hand.)
Whenever you cast a creature spell, create a 1/1 green and white Human Citizen creature token.
{3}{G}{W}: Creatures you control get +2/+2 and gain vigilance until end of turn.

Adeline, Resplendent Cathar

Vigilance
Adeline's power is equal to the number of creatures you control.
Whenever you attack, for each opponent, create a 1/1 white Human creature token that's tapped and attacking that player or a planeswalker they control.

Luminarch Aspirant

At the beginning of combat on your turn, put a +1/+1 counter on target creature you control.