Sphinx
Sphinxes are large, powerful creatures with lion-like bodies, human faces, and feathered wings. Some rival dragons in size and strength. Sphinxes are known for their cunning and vast intellect, and many never speak save in riddles. They are aligned primarily with blue magic, though some may be white and/or black. Sphinxes can be found on the worlds of Dominaria, Ravnica, Alara, Zendikar, and Mirrodin. Sphinx is the iconic creature for the color blue. [1]
The first card to bear the creature type was Petra Sphinx in Legends.
Alara
Sphinxes on Alara are highly revered and respected as leaders of their communities because of their vast knowledge. The Sphinx Crucius is said to have created Etherium, which shaped Esper into what it is now, and after the shortening of stores of Etherium, Sharuum showed them how to make it last longer. After the Sundering and prior to the Conflux, Sphinxes were found exclusively on Esper.
Mirrodin
There are a small number of sphinxes on Mirrodin. It is known that at least the Consecrated Sphinx has been compleated by the Phyrexians.
Ravnica
Ravnica is known to have sphinxes affiliated with the Azorius.
Serra's Realm
In an alternate reality, sphinxes populated the planeswalker Serra's realm instead of angels.
Theros
Theran sphinxes are primordial, mysterious beings with ancient knowledge. They have abstract thought patterns, so even when they are not trying to be enigmatic they still are. One, Medomai, is a prophet at Meletis, going into the city several times to warn of future events.
Zendikar
On Zendikar, Sphinxes are to be found in Sejiri and on the Jwar Isle, and most recently in Magosi as well.