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Lieutenant Zac is an inexperienced Colonial Warrior and Viper pilot assigned to Galactica, which is commanded by his father, Commander Adama. He is the youngest of Adama's and Ila's children; his older siblings, Apollo and Athena, are also assigned to Galactica.
Zac works with Starbuck to convince his brother, Apollo, that Starbuck was too ill to go on patrol, suggesting that Zac take patrol instead. Apollo sees through the ruse and allows Zac to come anyway.
Zac's Viper is damaged and unable to keep up with his brother. Zac encourages Apollo to go ahead to warn the battlestar fleet of the massive Cylon fighter squadron.
Zac's fighter falls behind as he is chased by the Cylons. While in sight of the battlestar fleet but with no Vipers scrambled to assist, despite Commander Adama's pleas for fleet defensive measures to President Adar, Zac's Viper is destroyed. This makes him the first known casualty of the decisive, genocidal attack on the Twelve Colonies (Saga of a Star World).