"The Heavy Flail has the ability to deal massive crushing power while still being just as unpredictable as the normal flail. It sacrifices speed for its power, but makes up for it in intimidation"
Instead of having a stab, it uses a shield bash akin to the one used by Javelin-wielding Archers.
It was implemented in the January 2013 patch.
The Warhammer does a bit more damage, is twice as long, and is only slightly slower. However, this weapon's biggest benefit is its unpredictability due to its animation. NOTE: weapon stat values shown in game are general approximations, as the range of the flail is also unpredictable. Both Flails no longer have to be wielded along with the Heater Shield .