Tripping and Disarming (4e Variant Rule)
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 Tripping and Disarming
|Halberds have back-hooks for pulling riders from their mounts.|
Tripping and disarming in combat was an option in 3.5e, but was removed in 4e. Tripping attacks were moved into class powers, and disarming was abstracted away: in terms of the dramatic flow, disarming an enemy is usually signals the defeat of a foe. That is, it is part of the narrative when you reduce an enemy to 0 hit points (you role-play this as flipping the sword out of their hands, and they surrender).
However, there are many medieval weapons with hooks and chains that are specifically designed to entangle weapons, wrench away shields, pull riders from horses and to trip foes: the ranseur and spetum, the hook sword and halberd. There is also design space in 4e for these functions: we have the bullrush, weapon properties, and status conditions. With a little abstraction, we can spice up combat with these interesting weapons.
 Status Conditions
Powers that apply these conditions will apply them much like other condiditions: they will usually last either until the end of the attacker's next turn, or until the victim passes a saving throw. The victim recovers their weapon or shield as soon as the condition ends. Note that the weapon itself has no definite location during this time. It may have been flung to the floor, or they may still be holding it but in an entangled or otherwise disengaged state. Ranged weapon attacks can still be made with the penalty: the victim may be hurling their sling stones and arrows by hand, or still able to throw their javelins but in an inconvenienced state (struggling with their straps and brackets for example).
Also, since monsters statblocks do not distinguish between spell-like powers that use implements and powers that are inherent (i.e. they do not use the implement keyword), it is not possible to disarm an implement.
A creature that is disarmed suffers a -2 penalty to attack rolls and a -2 penalty to damage rolls on its attacks with the weapon keyword. The damage penalty increases to -4 for paragon tier creatures, and to -6 for epic level creatures.
A creature that is deshielded suffers a -1 penalty to AC and Reflex if it is equipped with a shield. It has no effect on creatures that are not equipped with a shield.
 Attack Powers
Weapons with this property can be used to make a disarm attck.
Weapons with this property can be used to make a trip attack.
Official weapons that can be considered to have the tripping property: Halberd
Homebrew weapons that have the tripping property: Guisarme, Ankus, Lochaber axe, Talenta sharrash, Dwarven warpike, Gyrespike
Official weapons that can be considered to have the disarming property: None
Homebrew weapons that have the disarming property: Ranseur, Spetum, Gyrespike