Swooping Protector

Flash
Flying
Swooping Protector enters with a shield counter on it. (If it would be dealt damage or destroyed, remove a shield counter from it instead.)

Conclave Mentor

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 that creature instead.
When Conclave Mentor dies, you gain life equal to its power.

Metastatic Evangel

Whenever another nontoken creature you control enters, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Brotherhood Outcast

When Brotherhood Outcast enters, choose one —
• Return target Aura or Equipment card with mana value 3 or less from your graveyard to the battlefield.
• Put a shield counter on target creature. (If it would be dealt damage or destroyed, remove a shield counter from it instead.)

Conclave Sledge-Captain

Backup 1, backup 1, backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following abilities until end of turn. Each backup ability triggers separately.)
Trample
Whenever this creature deals combat damage to a player, put that many +1/+1 counters on it.

Family's Favor

Whenever you attack, put a shield counter on target attacking creature. Until end of turn, it gains "Whenever this creature deals combat damage to a player, remove a shield counter from it. If you do, draw a card." (If a creature with a shield counter on it would be dealt damage or destroyed, remove a shield counter from it instead.)

Master Chef

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

Rampant Growth

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

Voice of the Vermin

Voice of the Vermin enters with a shield counter on it. (If it would be dealt damage or destroyed, remove a shield counter from it instead.)
Whenever Voice of the Vermin attacks, target creature you control has base power and toughness 4/4 until end of turn.

Diamond City

Diamond City enters with a shield counter on it. (If it would be dealt damage or destroyed, remove a shield counter from it instead.)
{T}: Add {C}.
{T}: Move a shield counter from Diamond City onto target creature. Activate only if two or more creatures entered the battlefield under your control this turn.

Proud Pack-Rhino

When Proud Pack-Rhino enters, choose one —
• Put a shield counter on target permanent. (If it would be dealt damage or destroyed, remove a shield counter from it instead.)
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Llanowar Elves

Titan of Industry

Reach, trample
When Titan of Industry enters, choose two —
• Destroy target artifact or enchantment.
• Target player gains 5 life.
• Create a 4/4 green Rhino Warrior creature token.
• Put a shield counter on a creature you control.

Dapper Shieldmate

Dapper Shieldmate enters with a shield counter on it. (If it would be dealt damage or destroyed, remove a shield counter from it instead.)
During your turn, Dapper Shieldmate gets +2/+0.

Grateful Apparition

Flying
Whenever Grateful Apparition deals combat damage to a player or planeswalker, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Elspeth Resplendent

+1: Choose up to one target creature. Put a +1/+1 counter and a counter from among flying, first strike, lifelink, or vigilance on it.
−3: Look at the top seven cards of your library. You may put a permanent card with mana value 3 or less from among them onto the battlefield with a shield counter on it. Put the rest on the bottom of your library in a random order.
−7: Create five 3/3 white Angel creature tokens with flying.

Boon of Safety

Put a shield counter on target creature. (If it would be dealt damage or destroyed, remove a shield counter from it instead.)
Scry 1.

Contractual Safeguard

Addendum — If you cast this spell during your main phase, put a shield counter on a creature you control. (If it would be dealt damage or destroyed, remove a shield counter from it instead.)
Choose a kind of counter on a creature you control. Put a counter of that kind on each other creature you control.

Sanctuary Warden

Flying
Sanctuary Warden enters with two shield counters on it.
Whenever Sanctuary Warden enters or attacks, you may remove a counter from a creature or planeswalker you control. If you do, draw a card and create a 1/1 green and white Citizen creature token.

Good-Fortune Unicorn

Whenever another creature you control enters, put a +1/+1 counter on that creature.

Managorger Hydra

Trample
Whenever a player casts a spell, put a +1/+1 counter on Managorger Hydra.

Lae'zel, Vlaakith's Champion

If you would put one or more counters on a creature or planeswalker you control or on yourself, put that many plus one of each of those kinds of counters on that permanent or player instead.
Choose a Background (You can have a Background as a second commander.)

Rhox Pummeler

Rhox Pummeler enters with a shield counter on it. (If it would be dealt damage or destroyed, remove a shield counter from it instead.)
Rhox Pummeler has trample as long as it has a shield counter on it.