During the prologue, kill the woman with the spear while playing as Balathu. (Also choose to '
Fight' later).
For the rest of the playthrough, keep at least Salim, Jason and Nick alive. I would keep every character alive up until the city part for this achievement personally.
Have Nick '
Retreat' when planting the bombs and then as Jason choose '
Forecful' to go rescue Salim. After rescuing Salim fail the next QTE when Balathu throws his spear. This will grant the achievement after Jason dies.
Note: If you have a save file with all characters survived and Balathu killed the woman/stood to fight in the prologue you can just load up the chapter
"The Vault" and then follow the method rather than a full playthrough.
Furthermore, it is also possible to get Rachel killed by Balathu's spear in
"The Assault". If you wish to follow this method, shoot the 'demon' on top of Rachel as Salim. Then pass Rachel's QTEs to save Eric but fail the one to dodge Balathu's Spear.
Credit to ThePugHybrid for their
guide.