Artoomis
First Post
From the SRD:
It's NOT optional, but core standard. I think it was that way in 3.0 as well.
Massive Damage: If you ever sustain a single attack deals 50 points of damage or more and it doesn’t kill you outright, you must make a DC 15 Fortitude save. If this saving throw fails, you die regardless of your current hit points. If you take 50 points of damage or more from multiple attacks, no one of which dealt 50 or more points of damage itself, the massive damage rule does not apply.
It's NOT optional, but core standard. I think it was that way in 3.0 as well.