Rhythm of the Wild

Creature spells you control can't be countered.
Nontoken creatures you control have riot. (They enter the battlefield with your choice of a +1/+1 counter or haste.)

Boros Locket

{T}: Add {R} or {W}.
{R/W}{R/W}{R/W}{R/W}, {T}, Sacrifice Boros Locket: Draw two cards.

Boros Guildgate

Boros Guildgate enters the battlefield tapped.
{T}: Add {R} or {W}.

Faeburrow Elder

Vigilance
Faeburrow Elder gets +1/+1 for each color among permanents you control.
{T}: For each color among permanents you control, add one mana of that color.

Rubblebelt Rioters

Haste
Whenever Rubblebelt Rioters attacks, it gets +X/+0 until end of turn, where X is the greatest power among creatures you control.

Knight of Autumn

When Knight of Autumn enters the battlefield, choose one —
• Put two +1/+1 counters on Knight of Autumn.
• Destroy target artifact or enchantment.
• You gain 4 life.

Domri, Anarch of Bolas

Creatures you control get +1/+0.
+1: Add {R} or {G}. Creature spells you cast this turn can't be countered.
−2: Target creature you control fights target creature you don't control.

Emmara, Soul of the Accord

Whenever Emmara, Soul of the Accord becomes tapped, create a 1/1 white Soldier creature token with lifelink.

Tolsimir, Friend to Wolves

When Tolsimir, Friend to Wolves enters the battlefield, create Voja, Friend to Elves, a legendary 3/3 green and white Wolf creature token.
Whenever a Wolf enters the battlefield under your control, you gain 3 life and that creature fights up to one target creature you don't control.

Rienne, Angel of Rebirth

Flying
Other multicolored creatures you control get +1/+0.
Whenever another multicolored creature you control dies, return it to its owner's hand at the beginning of the next end step.

Domri, Chaos Bringer

+1: Add {R} or {G}. If that mana is spent on a creature spell, it gains riot. (It enters the battlefield with your choice of a +1/+1 counter or haste.)
−3: Look at the top four cards of your library. You may reveal up to two creature cards from among them and put them into your hand. Put the rest on the bottom of your library in a random order.
−8: You get an emblem with "At the beginning of each end step, create a 4/4 red and green Beast creature token with trample."

Domri's Ambush

Put a +1/+1 counter on target creature you control. Then that creature deals damage equal to its power to target creature or planeswalker you don't control.

Gruul Spellbreaker

Riot (This creature enters the battlefield with your choice of a +1/+1 counter or haste.)
Trample
As long as it's your turn, you and Gruul Spellbreaker have hexproof.

Boros Challenger

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
{2}{R}{W}: Boros Challenger gets +1/+1 until end of turn.

Tajic, Legion's Edge

Haste
Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Prevent all noncombat damage that would be dealt to other creatures you control.
{R}{W}: Tajic, Legion's Edge gains first strike until end of turn.

Aurelia, Exemplar of Justice

Flying
Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
At the beginning of combat on your turn, choose up to one target creature you control. Until end of turn, that creature gets +2/+0, gains trample if it's red, and gains vigilance if it's white.

Ravager Wurm

Riot (This creature enters the battlefield with your choice of a +1/+1 counter or haste.)
When Ravager Wurm enters the battlefield, choose up to one —
• Ravager Wurm fights target creature you don't control.
• Destroy target land with an activated ability that isn't a mana ability.

Trostani Discordant

Other creatures you control get +1/+1.
When Trostani Discordant enters the battlefield, create two 1/1 white Soldier creature tokens with lifelink.
At the beginning of your end step, each player gains control of all creatures they own.

Outlaws' Merriment

At the beginning of your upkeep, choose one at random. Create a red and white creature token with those characteristics.
• 3/1 Human Warrior with trample and haste.
• 2/1 Human Cleric with lifelink and haste.
• 1/2 Human Rogue with haste and "When this creature enters the battlefield, it deals 1 damage to any target."