Sigarda

Sigarda is an Angel from Innistrad associated with purity and birth and the protection of humans. Also known as the Host of Herons, she is the leader of the Flight of Herons and wields a heron-shaped scythe. She is a sister of Bruna, Gisela, and Liesa, and fought Avacyn and her corrupted angels, including two of her sisters after their corruption.

The Four Sisters
Sigarda, Bruna, Gisela and Liesa are described as sisters and are older than Avacyn. Unlike the more loyal Gisela, Sigarda felt unconnected to Avacyn, due to the latter's own detachment from the other angels, though she respected her power as a leader.

The Flight of Herons
Sigarda and the other angels of the Flight of Herons are connected to birth and purity and are associated with the New Moon season. Their magic is said to ward humans against harm in life (as opposed to the Alabaster host, which wards against harm in death). Most of the angels from this flight helped in the efforts of humans against the werewolves.

Survivor
In the Hunter's Moon the year after Avacyn was restored, Sigarda was approached by Gisela and Bruna in her own solar. The two flanked her as Avacyn manifested before her. By now fully corrupted, Avacyn advocated genocide against Innistrad's humans, which Sigarda regarded with fear and disgust. She didn't respond to Avacyn's insane statements, but Avacyn sensed her hesitation and blew up her solar's roof, implying a threat should she fail to comply. Already resentful towards Avacyn for the death of Liesa, Sigarda cried and vowed to fight the archangel.

Upon discovering what her sisters had become, Sigarda could only weep. In Thraben, she chose to fight against the corrupted angels, aiding the Cathar Thalia in slaying the monstrosity that was comprised of her former sisters. Multiple humans turned to worship Sigarda for protection since she alone had not turned her host against them.