The Lucky Saradomin godsword (passive) is created by using a Lucky Saradomin godsword on the altar in Commander Zilyana's room. This process can be repeated to turn the sword back to normal. If this sword is destroyed, it can be reclaimed from Diango, albeit in its non-passive version. The passive effect replaces the special attack.
It has a passive effect that can be toggled on by using it on the altar within the boss room of Saradomin's Encampment (the room in which Commander Zilyana is located), however, entering Saradomin's Encampment requires 70 Agility. The effect has a 25% chance of activating upon a successful hit, healing 3% of your maximum life points and recovering 3% of your maximum prayer points with each successful hit.
The special attack is more useful for emergency heal situations and can heal a lot of life points instantly, especially if used under damage boosting abilities such as Berserk. The passive effect heals more consistently and has a comparable life points restore but substantially better prayer points restore. However, for players with access to superior weaponry (such as drygore weaponry) who do not wish to use a level 75 weapon (which is required in order to benefit from the passive effect), the special attack is preferable.