Naban, Dean of Iteration

Legendary Creature — Human Wizard (2/1)

If a Wizard entering the battlefield under your control causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Narcomoeba

Creature — Illusion (1/1)

Flying
When Narcomoeba is put into your graveyard from your library, you may put it onto the battlefield.

Neurok Familiar

Creature — Bird (1/1)

Flying
When Neurok Familiar enters the battlefield, reveal the top card of your library. If it's an artifact card, put it into your hand. Otherwise, put it into your graveyard.

Nightveil Sprite

Creature — Faerie Rogue (1/2)

Flying
Whenever Nightveil Sprite attacks, surveil 1. (Look at the top card of your library. You may put it into your graveyard.)

Oaken Siren

Artifact Creature — Siren Pirate (1/2)

Flying, vigilance
: Add . Spend this mana only to cast an artifact spell or activate an ability of an artifact source.

Oboro Breezecaller

Creature — Moonfolk Wizard (1/1)

Flying
, Return a land you control to its owner's hand: Untap target land.

Oculus

Creature — Phyrexian Homunculus (1/1)

When Oculus dies, you may draw a card.

Oglor, Devoted Assistant

Legendary Creature — Homunculus (1/1)

At the beginning of your upkeep, look at the top two cards of your library, then put one of them into your graveyard.
Whenever a creature card is put into your graveyard from your library or hand, it perpetually gains "When this card leaves your graveyard, create a tapped 2/2 black Zombie creature token."

Omenspeaker

Creature — Human Wizard (1/3)

When Omenspeaker enters the battlefield, scry 2. (Look at the top two cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)

Overtaker

Creature — Merfolk Spellshaper (1/1)

, , Discard a card: Untap target creature and gain control of it until end of turn. That creature gains haste until end of turn.

Owl Familiar

Creature — Bird (1/1)

Flying
When Owl Familiar enters the battlefield, draw a card, then discard a card.

Palace Familiar

Creature — Bird (1/1)

Flying
When Palace Familiar dies, draw a card.

Parcel Myr

Artifact Creature — Clue Myr (2/1)

, Sacrifice Parcel Myr: Draw a card.

Pelargir Survivor

Creature — Human Peasant (1/3)

: Add one mana of any color. Spend this mana only to cast an instant or sorcery spell.
, : Target player mills three cards. (They put the top three cards of their library into their graveyard.)

Persistent Petitioners

Creature — Human Advisor (1/3)

, : Target player mills a card. (They put the top card of their library into their graveyard.)
Tap four untapped Advisors you control: Target player mills twelve cards.
A deck can have any number of cards named Persistent Petitioners.

Phantasmal Image

Creature — Illusion (0/0)

You may have Phantasmal Image enter the battlefield as a copy of any creature on the battlefield, except it's an Illusion in addition to its other types and it has "When this creature becomes the target of a spell or ability, sacrifice it."

Pixie Guide

Creature — Faerie (1/3)

Flying
Grant an Advantage — If you would roll one or more dice, instead roll that many dice plus one and ignore the lowest roll.

Plated Seastrider

Creature — Beast (1/4)

Pollywog Symbiote

Creature — Frog (1/3)

Each creature spell you cast costs less to cast if it has mutate.
Whenever you cast a creature spell, if it has mutate, draw a card, then discard a card.

Prize Wall

Creature — Wall (0/4)

Defender
, : You get .
, : You may put a sticker on a nonland permanent you own. Activate only as a sorcery.