#ixidor

"Akroma is one of the most famous figures of The Mirari Conjecture, even though she did not appear until a little before the Legion Wars. She was created in a dream by Ixidor, (who had become Lowalyn's Avatar, the Numena Mage who long ago banished Dromar) using his literal right arm. Her name means "without color", named as she appears like his lost love Nivea but devoid of the color of her life."

"Her purpose was to slay the former Pardic Barabrian and sister to Kamahl Jeska who had been turned into an Avatar of Death by the Cabal and taken the name Phage. Phage had killed Nivea in a pit fight against Ixidor. Even after Ixidor's apparent death, Akroma sought to complete her master's vengeance and her clash with Phage let to the rebirth of Karona, the False God and embodiment of Dominaria's Magic."

Ixidor’s ability can target any face-down creature you control, including all manifested cards.

If the face-down card is a permanent card, then it turns face up and is on the battlefield as normal when Ixidor’s ability resolves. Note that the permanent was already on the battlefield, so any “enters the battlefield” triggered abilities or replacement effects won’t have happened to the card. This includes the starting loyalty counters of planeswalkers and so all planeswalkers turned face up this way will die immediately.

If the face-down card is an instant or sorcery card, then it can never be face up on the battlefield and so you’ll just reveal that it’s an instant or sorcery card and leave it face down as a blank creature.