Shapesharer

Changeling (This card is every creature type.)
{2}{U}: Target Shapeshifter becomes a copy of target creature until your next turn.

Unesh, Criosphinx Sovereign

Flying
Sphinx spells you cast cost {2} less to cast.
Whenever Unesh, Criosphinx Sovereign or another Sphinx you control enters, reveal the top four cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

Birthing Boughs

{4}, {T}: Create a 2/2 colorless Shapeshifter creature token with changeling. (It has every creature type.)

Universal Automaton

Changeling (This card is every creature type.)

Ponder

Look at the top three cards of your library, then put them back in any order. You may shuffle.
Draw a card.

Mothdust Changeling

Changeling (This card is every creature type.)
Tap an untapped creature you control: Mothdust Changeling gains flying until end of turn.

Amoeboid Changeling

Changeling (This card is every creature type.)
{T}: Target creature gains all creature types until end of turn.
{T}: Target creature loses all creature types until end of turn.