Littjara Kinseekers

Changeling (This card is every creature type.)
When this creature enters, if you control three or more creatures that share a creature type, put a +1/+1 counter on this creature, then scry 1.

Sakashima the Impostor

You may have Sakashima the Impostor enter as a copy of any creature on the battlefield, except its name is Sakashima the Impostor, it's legendary in addition to its other types, and it has "{2}{U}{U}: Return Sakashima the Impostor to its owner's hand at the beginning of the next end step."

Riptide Shapeshifter

{2}{U}{U}, Sacrifice this creature: Choose a creature type. Reveal cards from the top of your library until you reveal a creature card of that type. Put that card onto the battlefield and shuffle the rest into your library.

Homeward Path

{T}: Add {C}.
{T}: Each player gains control of all creatures they own.

Braids, Conjurer Adept

At the beginning of each player's upkeep, that player may put an artifact, creature, or land card from their hand onto the battlefield.

Sakashima of a Thousand Faces

You may have Sakashima enter as a copy of another creature you control, except it has Sakashima's other abilities.
The "legend rule" doesn't apply to permanents you control.
Partner (You can have two commanders if both have partner.)

Mistform Stalker

{1}: This creature becomes the creature type of your choice until end of turn.
{2}{U}{U}: This creature gets +2/+2 and gains flying until end of turn.

Lifecraft Engine

As this Vehicle enters, choose a creature type.
Vehicle creatures you control are the chosen creature type in addition to their other types.
Each creature you control of the chosen type other than this Vehicle gets +1/+1.
Crew 3

Eon Frolicker

Flying
When this creature enters, if you cast it, target opponent takes an extra turn after this one. Until your next turn, you and planeswalkers you control gain protection from that player. (You and planeswalkers you control can't be targeted, dealt damage, or enchanted by anything controlled by that player.)

Mistform Warchief

Creature spells you cast that share a creature type with this creature cost {1} less to cast.
{T}: This creature becomes the creature type of your choice until end of turn.

Mirror of the Forebears

As this artifact enters, choose a creature type.
{1}: Until end of turn, this artifact becomes a copy of target creature you control of the chosen type, except it's an artifact in addition to its other types.

Unnatural Selection

{1}: Choose a creature type other than Wall. Target creature becomes that type until end of turn.

Dictate of Kruphix

Flash (You may cast this spell any time you could cast an instant.)
At the beginning of each player's draw step, that player draws an additional card.

Benthic Explorers

{T}, Untap a tapped land an opponent controls: Add one mana of any type that land could produce.

Mistform Wall

This creature has defender as long as it's a Wall.
{1}: This creature becomes the creature type of your choice until end of turn.