Fortitude
The basic effect remains the same: each dot gives you one die to add to all soak rolls, including rolls vs. aggravated damage that cannot be soaked normally.
Level 1 -- Upon learning the rudiments of Fortitude, the vampire becomes so tough that they become markedly better at avoiding damage. Ones no longer subtract from their successes on soak rolls.
Level 2 -- There is no additional effect at this level.
Level 3 -- At this level the vampire can shatter weapons if they hit hard enough. Their opponent must get five or more sucesses to damage, and the Kindred with Fortitude must score five or more successes to soak the damage. If this happens the weapon in question is broken.
Level 4 -- The Kindred becomes harder to kill. They can still be injured severely, but they hang on to life a little bit longer than most other Vampires. The Kindred gains an extra crippled health level.
Level 5 -- The Kindred becomes naturally tougher and is simply better at resisting all damage. The difficulties for all soak rolls are reduced by 1. So soaking normal damage is now difficulty 5.