From Texas Chain Saw Massacre Wiki
Savagery: This Attribute directly affects the amount of damage you deal with melee hits, but should not be seen as simple strength. Think of Savagery as a proficiency level for killing in game, used in conjunction with Endurance as a way to determine the full potential for damage dealt.
Harvesting: Harvesting affects the amount of blood you gain for Grandpa when interacting with Victims. It does not, however, affect the amount of blood gained from buckets around the map. Melee hits, grapples with Victims, and executions are the specific interactions that can fill your blood vial, dependent on your Harvesting stat.
Endurance: Similar to the Victims Attribute, Endurance affects the stamina drain and recharge rate. On the Family side, however, melee strikes also drain stamina, making the Endurance Attribute important for dealing damage as well as mobility.
