When swung with sufficient strength, heavy weapons were able to smash through attempts to parry with smaller weapons, and opponents caught under the full weight of the blow mostly collapsed or could even drop their weapons.
Heavy weapons could only be countered by long or other heavy weapons, as well as the Hidden Blade, though the shorter timing window involved made the latter more difficult and riskier.
A Smash took a long time to build up, during which Ezio was vulnerable to interruption. However, when a fully charged Smash connected, it would break through enemy defenses to cause a large amount of damage. It could not be parried, and the victim would be disarmed, or possibly have their long weapon broken if they wielded one.
When in Rome, the Smash skill was no longer available to Ezio, and had instead been replaced by the ability to throw heavy weapons at enemies. This could be done to perform instant kills, up to the distance of around ten meters away.
Accompanying this, Ezio could pick up the heavy weapon after throwing it, though if he picked up a short or medium weapon from a deceased guard, his weapon would change over to that, and the Assassin would have to go to a blacksmith to re-equip the heavy weapon.
The maximum amount of combo hits with a heavy weapon was three.
Ezio could disarm a weapon from Brutes in the first attempt, whereas it could take several attempts to disarm Elite or Leader guards.
Heavy weapons were the most common weapons used by mercenaries.
Taunting was an effective method to disarm tougher guards such as Brutes or Papal Guards, as it made them attack faster and gave Ezio more chances to disarm them.
Assassin recruits below the rank of Assassino could wield heavy weapons, and although these were described as axes in the recruit's training interface, they could manifest themselves as two-handed swords as well.
In Brotherhood, although Ezio could no longer perform the Smash skill, enemy guards still could. They could not, however, perform the disarm move.
Occasionally, whenever a heavy weapon was thrown at a guard that was in mid-air, through freerunning after pickpockets, it would stay in their head and they would stand still. From then on, the guard would appear dead and wouldn't attack Ezio, but when the Assassin removed his heavy weapon from the body, the weapon would fall to the ground and could be retrieved as usual.
In Brotherhood, heavy weapons lacked the ability to counter-attack other heavy or long weapon users, except during an execution or counter-kill animation. Despite this, long weapons retained the ability to counter other long or heavy weapons.
In Revelations, heavy weapons could be countered against with medium weapons.
The Broadsword in Revelations, although listed as a heavy weapon, was wielded like a medium weapon. However the sound effects in kill animations were a mix of both medium and heavy weapon sounds.
In Brotherhood andRevelations, heavy weapons no longer became lodged into enemies when counter-killing them, allowing Ezio to keep using them for the duration of the battle, unless they were thrown.