[charlieluce]

Since the Blood Wolf Animal Companion is defined by how it differs from the regular Wolf, you can easily modify a Wolf Animal Companion to represent a Blood Wolf:

1) Select a Wolf Animal Companion.
2) Under Modifications > Added Abilities > Permanent Abilities add Darkvision.
3) Under Modifications > Adjustments > Permanent Adjustments > Resources add Hit Points and set it to +2.
4) Under Modifications > Adjustments > Permanent Adjustments > Resources add Skill Increases, set it to +1 Trained, then under Skills set Intimidate to Trained.
5) Under Modifications > Adjustments > Permanent Adjustments >Skills/Proficiencies add Override Proficiency Level and set it to Untrained for Survival.
6) Under Profile > Race Appears As enter Blood Wolf.

Hope that helps!