The abyssal orb is an off-hand Magic weapon that requires level 75 to wield. It is dropped by abyssal demons, but only for players who have them as their Slayer assignment. It was first announced in Behind the Scenes - February 2014. Both the abyssal orb and the abyssal wand are able to cast slayer dart and have the ability to save runes, much like the staff of light. The improved demon drop tables were decided in a Power to the Players poll.
In a FAQ, the drop rate of the abyssal wand and orb was confirmed to be much rarer than the abyssal whip's drop rate of 1/1024.
- ^ Mod Slayer. "Treasure Hunter & Demon FAQ". RuneScape Forums.