Successfully complete the indicated task to unlock the corresponding bonus:

Agent Muriel Green Successfully complete "The Den of Souls" on the Hard difficulty setting
Antadurunnu Successfully complete "The God Seal" on the Hard difficulty setting
Arnold Leech Successfully complete "Al Khali" on the Easy or Normal difficulty setting

Bishop Malthus St. Claire Successfully complete "Crusades" on the Easy or Normal difficulty setting
Blind Behemoth Successfully complete "Morituri te salutant" on the Hard difficulty setting without being incapacitated
Brother William of Auxere Successfully complete "Motley Crew" on the Hard difficulty setting

Centurion Textius Longinus Successfully complete "Decadence" on the Hard difficulty setting without being incapacitated
Child Crusader Successfully complete "Crusades" on the Easy or Normal difficulty setting
Corpses Behemoth Successfully complete "River of Blood" on the Hard difficulty setting
Cpl. Simone Cole Successfully complete "The Tomb" on the Hard difficulty setting
Cpt. Devin Ross Kill 50 enemies using melee attacks
Cpt. Xavier Jones Successfully complete "Man Down" on the Hard difficulty setting
Crossbowman Crusader Successfully complete "Tortured Souls" on the Hard difficulty setting
Cultist Kill 100 enemies using melee attacks

Deceased Devin Ross Successfully complete "Still With You" on the Hard difficulty setting

Enlil Successfully complete "Spiritual Guide" on the Hard difficulty setting
Exlposive Cultist Disintegrate 50 enemies

Flamethrower Disintegrate 100 enemies
Fr. Paul Rawlings Pop 100 heads

Gladiator Successfully complete "Temple of Pain" on the Hard difficulty setting
Governor Cassus Vicus Successfully complete "Rome" on the Easy or Normal difficulty setting
Grenadier Kill 100 enemies using Ghost Bullet

Inanna Successfully complete "Skin" on the Hard difficulty setting

Ki Successfully complete "Flesh" on the Hard difficulty setting

Legionary Successfully complete "The Low Road" on the Hard difficulty setting
Lt. Abigail Black Kill 50 enemies using Ghost Bullet

Nanna Successfully complete "Blood" on the Hard difficulty setting
Ninlil Successfully complete "Skin" on the Hard difficulty setting without being incapacitated

Operation: Godseal Successfully complete "Exorcism" on the Hard difficulty setting

Psychic Commander Successfully complete "World War 2" on the Easy or Normal difficulty setting
Pyxis Prima Successfully complete "Sumeria" on the Easy or Normal difficulty setting

Sgt. Frank Delgado Pop 50 heads
Sgt. Wilhelmina "Billie" Church Successfully complete "Al Khali" on the Hard difficulty setting
Sir Richard de Gray Successfully complete "Out of the Frying Pan" on the Hard difficulty setting
Sumerian Puppet Successfully complete "Flesh" on the Hard difficulty setting without being incapacitated

The Jericho Team Successfully complete "Rivers of Blood" on the Hard difficulty setting without being incapacitated

Utu Successfully complete "Blood" on the Hard difficulty setting without being incapacitated

Warrior Crusader Successfully complete "Sewers" on the Hard difficulty setting