Agatha's Soul Cauldron

You may spend mana as though it were mana of any color to activate abilities of creatures you control.
Creatures you control with +1/+1 counters on them have all activated abilities of all creature cards exiled with Agatha's Soul Cauldron.
{T}: Exile target card from a graveyard. When a creature card is exiled this way, put a +1/+1 counter on target creature you control.

Aurelia, the Warleader

Flying, vigilance, haste
Whenever Aurelia, the Warleader attacks for the first time each turn, untap all creatures you control. After this phase, there is an additional combat phase.

Collective Effort

Escalate—Tap an untapped creature you control. (Pay this cost for each mode chosen beyond the first.)
Choose one or more —
• Destroy target creature with power 4 or greater.
• Destroy target enchantment.
• Put a +1/+1 counter on each creature target player controls.

Ironpaw Aspirant

When Ironpaw Aspirant enters, put a +1/+1 counter on target creature.

Restless Bivouac

Restless Bivouac enters tapped.
{T}: Add {R} or {W}.
{1}{R}{W}: Restless Bivouac becomes a 2/2 red and white Ox creature until end of turn. It's still a land.
Whenever Restless Bivouac attacks, put a +1/+1 counter on target creature you control.

Angelfire Ignition

Put two +1/+1 counters on target creature. It gains vigilance, trample, lifelink, indestructible, and haste until end of turn.
Flashback {2}{R}{W} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Ajani Steadfast

+1: Until end of turn, up to one target creature gets +1/+1 and gains first strike, vigilance, and lifelink.
−2: Put a +1/+1 counter on each creature you control and a loyalty counter on each other planeswalker you control.
−7: You get an emblem with "If a source would deal damage to you or a planeswalker you control, prevent all but 1 of that damage."

Tempered Veteran

{W}, {T}: Put a +1/+1 counter on target creature with a +1/+1 counter on it.
{4}{W}{W}, {T}: Put a +1/+1 counter on target creature.

Temple of Civilization

(Transforms from Ojer Taq, Deepest Foundation.)
{T}: Add {W}.
{2}{W}, {T}: Transform Temple of Civilization. Activate only if you attacked with three or more creatures this turn and only as a sorcery.

Ojer Taq, Deepest Foundation

Vigilance
If one or more creature tokens would be created under your control, three times that many of those tokens are created instead.
When Ojer Taq dies, return it to the battlefield tapped and transformed under its owner's control.

Ojer Taq, Deepest Foundation // Temple of Civilization

Andúril, Narsil Reforged

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.)
Whenever equipped creature attacks, put a +1/+1 counter on each creature you control. If you have the city's blessing, put two +1/+1 counters on each creature you control instead.
Equip {3}

Ollenbock Escort

Vigilance
Sacrifice Ollenbock Escort: Target creature you control with a +1/+1 counter on it gains lifelink and indestructible until end of turn.

Siege Veteran

At the beginning of combat on your turn, put a +1/+1 counter on target creature you control.
Whenever another nontoken Soldier you control dies, create a 1/1 colorless Soldier artifact creature token.

Elder Cathar

When Elder Cathar dies, put a +1/+1 counter on target creature you control. If that creature is a Human, put two +1/+1 counters on it instead.

Hopeful Initiate

Training (Whenever this creature attacks with another creature with greater power, put a +1/+1 counter on this creature.)
{2}{W}, Remove two +1/+1 counters from among creatures you control: Destroy target artifact or enchantment.

Take Up the Shield

Put a +1/+1 counter on target creature. It gains lifelink and indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Basri's Solidarity

Put a +1/+1 counter on each creature you control.

Ainok Bond-Kin

Outlast {1}{W} ({1}{W}, {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 first strike.

Adeline, Resplendent Cathar

Vigilance
Adeline, Resplendent Cathar'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.

The Wandering Emperor

Flash
As long as The Wandering Emperor entered this turn, you may activate her loyalty abilities any time you could cast an instant.
+1: Put a +1/+1 counter on up to one target creature. It gains first strike until end of turn.
−1: Create a 2/2 white Samurai creature token with vigilance.
−2: Exile target tapped creature. You gain 2 life.

Ajani's Welcome

Whenever a creature you control enters, you gain 1 life.

Citadel Siege

As Citadel Siege enters, choose Khans or Dragons.
• Khans — At the beginning of combat on your turn, put two +1/+1 counters on target creature you control.
• Dragons — At the beginning of combat on each opponent's turn, tap target creature that player controls.

Explosive Entry

Destroy up to one target artifact. Put a +1/+1 counter on up to one target creature.

Brave the Sands

Creatures you control have vigilance.
Each creature you control can block an additional creature each combat.

Anim Pakal, Thousandth Moon

Whenever you attack with one or more non-Gnome creatures, put a +1/+1 counter on Anim Pakal, then create X 1/1 colorless Gnome artifact creature tokens that are tapped and attacking, where X is the number of +1/+1 counters on Anim Pakal.

Cathars' Crusade

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

Mondrak, Glory Dominus

If one or more tokens would be created under your control, twice that many of those tokens are created instead.
{1}{W/P}{W/P}, Sacrifice two other artifacts and/or creatures: Put an indestructible counter on Mondrak, Glory Dominus. ({W/P} can be paid with either {W} or 2 life.)

Angelic Intervention

Target creature or planeswalker you control gains protection from colorless or from the color of your choice until end of turn. If it's a creature, put a +1/+1 counter on it. (It can't be blocked, targeted, dealt damage, enchanted, or equipped by anything with that quality.)

Backup Agent

When Backup Agent enters, put a +1/+1 counter on target creature.

Ajani Goldmane

+1: You gain 2 life.
−1: Put a +1/+1 counter on each creature you control. Those creatures gain vigilance until end of turn.
−6: Create a white Avatar creature token. It has "This creature's power and toughness are each equal to your life total."

Lightshield Array

At the beginning of your end step, put a +1/+1 counter on each creature that attacked this turn.
Sacrifice Lightshield Array: Creatures you control gain hexproof and indestructible until end of turn.

Invasion of Gobakhan

(As a Siege enters, choose an opponent to protect it. You and others can attack it. When it's defeated, exile it, then cast it transformed.)
When Invasion of Gobakhan enters, look at target opponent's hand. You may exile a nonland card from it. For as long as that card remains exiled, its owner may play it. A spell cast this way costs {2} more to cast.