If they reach 20,000 rads (limit subject to perks) then the character will become feral. Ghoulified characters still absorb rads, and their rad limit is raised to 20,000 upon becoming a ghoul.Automatic acceptance into the Church of Atom or the Apostles of the Holy Light.PC will not be attacked by feral ghouls unless PC attacks first.Radiation also heals damaged or crippled limbs (Similar to Rad Regeneration Perk from Fallout 3).

PC may choose a trait at the beginning of the game that allows them to ghoulify rather than die when reaching 1,000 rads. To them, ghoulification rather than death by exposure to radiation is preferable – even lucky. If luck is equal to or greater than 9, then PC reaching 1,000 rads does not die, but experiences ghoulification. So – from that perspective ghoulification is unlucky

If Luck Stat is equal to or less than 2, then player character (PC) reaching 1,000 rads does not die, but experiences ghoulification (cutscene?)