Jhoira's Familiar
Artifact Creature — Bird
Flying
Historic spells you cast cost 
less to cast. (Artifacts, legendaries, and Sagas are historic.)
"You could say it was my pet project." —Jhoira
Kev Walker
Dominaria (DOM)
• #220Rulings
The last ability of Jhoira's Familiar doesn't reduce its own cost while you're casting it.
(wotc • 2020-08-07)
A spell is historic if it has the legendary supertype, the artifact card type, or the Saga enchantment subtype. Having two of those qualities doesn't make a spell more historic than another or provide an additional bonus—a spell either is historic or it isn't.
(wotc • 2020-08-07)
Rulings
The last ability of Jhoira's Familiar doesn't reduce its own cost while you're casting it.
(wotc • 2020-08-07)
A spell is historic if it has the legendary supertype, the artifact card type, or the Saga enchantment subtype. Having two of those qualities doesn't make a spell more historic than another or provide an additional bonus—a spell either is historic or it isn't.
(wotc • 2020-08-07)