Dark Jak is Jak's dark alter-ego seen in Jak II, Jak 3, and for a brief moment during The Lost Frontier. After being subjected to two years of dark eco experiments under the Dark Warrior Program at the hands of Baron Praxis in Haven City, Jak gained highly destructive powers coupled with high durability and strength, which he learned to control by help from an oracle in the Water Slums. Later in Jak 3, his dark form was matched by a light form which helped him balance his dark powers even further.