Lord Jyscal Guado

Flying
At the beginning of each end step, if you put a counter on a creature this turn, investigate. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

Cathar Commando

Flash
{1}, Sacrifice this creature: Destroy target artifact or enchantment.

Plains

Rinoa, Angel Wing

At the beginning of combat on your turn, creatures you control with flying get +1/+1 and gain vigilance until end of turn.
Whenever one or more attacking creatures you control die, you may return one of them to the battlefield tapped under its owner's control with a flying counter on it. Do this only once each turn.

Hushbringer

Flying, lifelink
Creatures entering or dying don't cause abilities to trigger.

Bulwark Ox

Whenever this creature attacks while saddled, put a +1/+1 counter on target creature.
Sacrifice this creature: Creatures you control with counters on them gain hexproof and indestructible until end of turn.
Saddle 1 (Tap any number of other creatures you control with total power 1 or more: This Mount becomes saddled until end of turn. Saddle only as a sorcery.)

Loyal Pegasus

Flying
This creature can't attack or block alone.

Emeria, the Sky Ruin

This land enters tapped.
At the beginning of your upkeep, if you control seven or more Plains, you may return target creature card from your graveyard to the battlefield.
{T}: Add {W}.

ED-E, Lonesome Eyebot

Flying
ED-E My Love — Whenever you attack, if the number of attacking creatures is greater than the number of quest counters on ED-E, put a quest counter on it.
{2}, Sacrifice ED-E: Draw a card, then draw an additional card for each quest counter on ED-E.

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Burnished Hart

{3}, Sacrifice this creature: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Selfless Spirit

Flying
Sacrifice this creature: Creatures you control gain indestructible until end of turn.

Bounty Agent

Vigilance
{T}, Sacrifice this creature: Destroy target legendary permanent that's an artifact, creature, or enchantment.

Cartographer's Hawk

Flying
When this creature deals combat damage to a player who controls more lands than you, return it to its owner's hand. If you do, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle.

Doorkeeper Thrull

Flash
Flying
Artifacts and creatures entering don't cause abilities to trigger.

Star Pupil

This creature enters with a +1/+1 counter on it.
When this creature dies, put its counters on target creature you control.

Dust Animus

Flying
If you control five or more untapped lands, this creature enters with two +1/+1 counters and a lifelink counter on it.
Plot {1}{W} (You may pay {1}{W} and exile this card from your hand. Cast it as a sorcery on a later turn without paying its mana cost. Plot only as a sorcery.)

Zack Fair

Zack Fair enters with a +1/+1 counter on it.
{1}, Sacrifice Zack Fair: Target creature you control gains indestructible until end of turn. Put Zack Fair's counters on that creature and attach an Equipment that was attached to Zack Fair to that creature.

Canoptek Wraith

Wraith Form — This creature can't be blocked.
Transdimensional Scout — When this creature deals combat damage to a player, you may pay {3} and sacrifice it. If you do, choose a land you control. Then search your library for up to two basic land cards which have the same name as the chosen land, put them onto the battlefield tapped, then shuffle.

Clarion Spirit

Whenever you cast your second spell each turn, create a 1/1 white Spirit creature token with flying.

Survey Mechan

Flying
Hexproof (This creature can't be the target of spells or abilities your opponents control.)
{10}, Sacrifice this creature: It deals 3 damage to any target. Target player draws three cards and gains 3 life. This ability costs {X} less to activate, where X is the number of differently named lands you control.

Remorseful Cleric

Flying
Sacrifice this creature: Exile target player's graveyard.

Guardian of the Great Door

As an additional cost to cast this spell, tap four untapped artifacts, creatures, and/or lands you control.
Flying

High Market

{T}: Add {C}.
{T}, Sacrifice a creature: You gain 1 life.

Warden of the Inner Sky

As long as this creature has three or more counters on it, it has flying and vigilance.
Tap three untapped artifacts and/or creatures you control: Put a +1/+1 counter on this creature. Scry 1. Activate only as a sorcery.

Major Teroh

Flying
{3}{W}{W}, Sacrifice Major Teroh: Exile all black creatures.

Enduring Bondwarden

Backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following ability until end of turn.)
When this creature dies, put its counters on target creature you control.

Dauntless Dismantler

Artifacts your opponents control enter tapped.
{X}{X}{W}, Sacrifice this creature: Destroy each artifact with mana value X.

Miner's Guidewing

Flying, vigilance
When this creature dies, target creature you control explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on that creature, then put the card back or put it into your graveyard.)

Witch's Oven

{T}, Sacrifice a creature: Create a Food token. If the sacrificed creature's toughness was 4 or greater, create two Food tokens instead. (They're artifacts with "{2}, {T}, Sacrifice this token: You gain 3 life.")

Duty Beyond Death

As an additional cost to cast this spell, sacrifice a creature.
Creatures you control gain indestructible until end of turn. Put a +1/+1 counter on each creature you control. (Damage and effects that say "destroy" don't destroy those creatures.)

Ruin-Lurker Bat

Flying, lifelink
At the beginning of your end step, if you descended this turn, scry 1. (You descended if a permanent card was put into your graveyard from anywhere.)