Urza's Incubator
Artifact
As this artifact enters, choose a creature type.
Creature spells of the chosen type cost 
less to cast.
"In my dark moments, I think Urza may have been more of a father to his creations than he ever was to his own son." —Tawnos
Randy Gallegos
Dominaria Remastered (DMR)
• #453Rulings
You choose a creature type right as it enters, before any continuous effects are applied or trigged abilities trigger.
(wotc • 2004-10-04)
Multiple Incubators are cumulative.
(wotc • 2004-10-04)
Rulings
You choose a creature type right as it enters, before any continuous effects are applied or trigged abilities trigger.
(wotc • 2004-10-04)
Multiple Incubators are cumulative.
(wotc • 2004-10-04)