When young, Killer returned to his father's Oglala people on the Pine Ridge Indian Reservation every summer, in order to know them and the land.
[7] The first Tribal College Fellow for Young People For, a youth leadership development organization, Killer expanded the group's tribal college network in 2009 into a Native American-led group called the Native Youth Leadership Alliance.
[10] He is noted as being the co-founder of Advance Native Political Leadership, a non-profit that aims to expand indigenous representation in elected and appointed offices across the United States.
[11] Concurrent to his political work, Killer has been involved as an actor and executive producer on two short films, Running Shadow and Istinma.
[12] He is in a relationship with Sarah Eagle Heart (Oglala Sioux), a non-profit leader, film producer and activist also from the Pine Ridge Reservation.