Brineborn Cutthroat

Flash (You may cast this spell any time you could cast an instant.)
Whenever you cast a spell during an opponent’s turn, put a +1/+1 counter on this creature.

Lurking Deadeye

Flash
When Lurking Deadeye enters, destroy target creature that was dealt damage this turn.

Shining Armor

Flash
When Shining Armor enters, attach it to target Knight you control.
Equipped creature gets +0/+2 and has vigilance.
Equip (: Attach to target creature you control. Equip only as a sorcery.)

Spectral Sailor

Flash (You may cast this spell any time you could cast an instant.)
Flying
: Draw a card.

Howl of the Hunt

Flash
Enchant creature
When Howl of the Hunt enters, if enchanted creature is a Wolf or Werewolf, untap that creature.
Enchanted creature gets +2/+2 and has vigilance.

Instruments of War

Flash
As Instruments of War enters, choose a creature type.
Creatures you control of the chosen type get +1/+1.

Wildborn Preserver

Flash (You may cast this spell any time you could cast an instant.)
Reach (This creature can block creatures with flying.)
Whenever another non-Human creature you control enters, you may pay . When you do, put X +1/+1 counters on this creature.

Restoration Angel

Flash
Flying
When this creature enters, you may exile target non-Angel creature you control, then return that card to the battlefield under your control.

Briarpack Alpha

Flash (You may cast this spell any time you could cast an instant.)
When Briarpack Alpha enters, target creature gets +2/+2 until end of turn.

Nightpack Ambusher

Flash
Other Wolves and Werewolves you control get +1/+1.
At the beginning of your end step, if you didn’t cast a spell this turn, create a 2/2 green Wolf creature token.

Spellstutter Sprite

Flash
Flying
When Spellstutter Sprite enters, counter target spell with mana value X or less, where X is the number of Faeries you control.

Pestermite

Flash
Flying
When Pestermite enters, you may tap or untap target permanent.

So Tiny

Flash
Enchant creature
Enchanted creature gets -2/-0. It gets -6/-0 instead as long as its controller has seven or more cards in their graveyard.

Vendilion Clique

Flash
Flying
When Vendilion Clique enters, look at target player’s hand. You may choose a nonland card from it. If you do, that player reveals the chosen card, puts it on the bottom of their library, then draws a card.

Undersea Invader

Flash (You may cast this spell any time you could cast an instant.)
Undersea Invader enters tapped.

Faerie Vandal

Flash (You may cast this spell any time you could cast an instant.)
Flying
Whenever you draw your second card each turn, put a +1/+1 counter on Faerie Vandal.

Havenwood Wurm

Flash (You may cast this spell any time you could cast an instant.)
Trample

Rescue Retriever

Flash
When Rescue Retriever enters, put a +1/+1 counter on each other Soldier you control.
Prevent all damage that would be dealt to other attacking Soldiers you control.

Zephyr Sentinel

Flash
Flying
When Zephyr Sentinel enters, return up to one other target creature you control to its owner’s hand. If it was a Soldier, put a +1/+1 counter on Zephyr Sentinel.

Wreck Hunter

Flash
When Wreck Hunter enters, choose target player. You create a tapped Powerstone token for each nonland card in that player’s graveyard that was put there from the battlefield this turn. (It’s an artifact with “: Add . This mana can’t be spent to cast a nonartifact spell.”)

Rescue Retriever

Flash
When Rescue Retriever enters, put a +1/+1 counter on each other Soldier you control.
Prevent all damage that would be dealt to other attacking Soldiers you control.

Goblin Firebomb

Flash
, , Sacrifice this artifact: Destroy target permanent.