Blizzard has revealed a few more legendary item mechanics on Reddit and the official forums.
The Butcher’s Sickle (1h Axe) – This item will now give players a chance to cast the Butcher’s sickle attack, dragging enemies to them. The tooltip should read something along the lines of: “X% chance to drag enemies to you when attacking.â€
The Gidbin (Ceremonial Dagger) will have a chance when attacking to summon forth a Fetish to fight for you. - Tooltip: "Chance to summon a Fetish when attacking."
Hellrack (Crossbow) – This weapon will have a chance to cast Jailer on enemies, rooting them to the ground. The tooltip should read something like: “Chance to root enemies to the ground when you hit them.â€