Altar of Dementia

Sacrifice a creature: Target player mills cards equal to the sacrificed creature's power.

Swift Reconfiguration

Flash
Enchant creature or Vehicle
Enchanted permanent is a Vehicle artifact with crew 5 and it loses all other card types. (It's not a creature unless it's crewed.)

Kathril, Aspect Warper

When Kathril enters, put a flying counter on any creature you control if a creature card in your graveyard has flying. Repeat this process for first strike, double strike, deathtouch, hexproof, indestructible, lifelink, menace, reach, trample, and vigilance. Then put a +1/+1 counter on Kathril for each counter put on a creature this way.

Rhonas the Indomitable

Deathtouch, indestructible
Rhonas can't attack or block unless you control another creature with power 4 or greater.
{2}{G}: Another target creature gets +2/+0 and gains trample until end of turn.

Birds of Paradise

Eternal Witness

When this creature enters, you may return target card from your graveyard to your hand.

Devoted Druid

{T}: Add {G}.
Put a -1/-1 counter on this creature: Untap this creature.

Nethroi, Apex of Death

Mutate {4}{G/W}{B}{B} (If you cast this spell for its mutate cost, put it over or under target non-Human creature you own. They mutate into the creature on top plus all abilities from under it.)
Deathtouch, lifelink
Whenever this creature mutates, return any number of target creature cards with total power 10 or less from your graveyard to the battlefield.

Cairn Wanderer

Changeling (This card is every creature type.)
As long as a creature card with flying is in a graveyard, this creature has flying. The same is true for fear, first strike, double strike, deathtouch, haste, landwalk, lifelink, protection, reach, trample, shroud, and vigilance.

Doom Whisperer

Flying, trample
Pay 2 life: Surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)

Golgari Thug

When this creature dies, put target creature card from your graveyard on top of your library.
Dredge 4 (If you would draw a card, you may mill four cards instead. If you do, return this card from your graveyard to your hand.)

Tainted Strike

Target creature gets +1/+0 and gains infect until end of turn. (It deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.)

Erebos, Bleak-Hearted

Indestructible
As long as your devotion to black is less than five, Erebos isn't a creature.
Whenever another creature you control dies, you may pay 2 life. If you do, draw a card.
{1}{B}, Sacrifice another creature: Target creature gets -2/-1 until end of turn.

Golgari Grave-Troll

This creature enters with a +1/+1 counter on it for each creature card in your graveyard.
{1}, Remove a +1/+1 counter from this creature: Regenerate this creature.
Dredge 6 (If you would draw a card, you may mill six cards instead. If you do, return this card from your graveyard to your hand.)

Akroma, Vision of Ixidor

Flying, first strike, vigilance, trample
At the beginning of each combat, until end of turn, each other creature you control gets +1/+1 if it has flying, +1/+1 if it has first strike, and so on for double strike, deathtouch, haste, hexproof, indestructible, lifelink, menace, protection, reach, trample, vigilance, and partner.
Partner

Leyline Prowler

Deathtouch, lifelink
{T}: Add one mana of any color.

Akroma, Angel of Wrath

Flying, first strike, vigilance, trample, haste, protection from black and from red

Luminous Broodmoth

Flying
Whenever a creature you control without flying dies, return it to the battlefield under its owner's control with a flying counter on it.

Questing Beast

Vigilance, deathtouch, haste
Questing Beast can't be blocked by creatures with power 2 or less.
Combat damage that would be dealt by creatures you control can't be prevented.
Whenever Questing Beast deals combat damage to an opponent, it deals that much damage to target planeswalker that player controls.

Dryad of the Ilysian Grove

You may play an additional land on each of your turns.
Lands you control are every basic land type in addition to their other types.

Worldly Tutor

Search your library for a creature card, reveal it, then shuffle and put the card on top.

Oketra the True

Double strike, indestructible
Oketra can't attack or block unless you control at least three other creatures.
{3}{W}: Create a 1/1 white Warrior creature token with vigilance.