Group Fighting (3.5e Variant Rule)
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As it is, for the most part combat is individuals fighting individuals or groups fighting groups, but those groups never actually work together, only attack the same opponent. This is my remedy, please put your ideas on the talk page, as this can certainly be expanded.
In any given group of combatants, any member of that group may initiate a group attack on an opponent within reach. Any allies who are also able to reach the opponent and who are still able to make an attack action this round may join this attack. This counts as a standard action for every attacker. Every attacker strikes at once, with either a normal attack or a full attack, at their choice. For every attacker after the first, each attacker gains a +1 bonus to hit.
Specific arrangements of soldiers have been shown to grant certain advantages over opponents.
In any given group of combatants, any member of that group may initiate a phalanx maneuver. Any allies who have a weapon (natural weapons count) and shield larger than a buckler and can still take a move action this round may join this maneuver. This counts as a move action for every participant. The participants form a straight line, with individual positions chosen by the group. The line faces one direction perpendicular to the direction it is pointing. Any nonflying and nonburrowing creature who attempts to break through the line from the front must make a successful overrun attack against one of the members of the line. However, instead of only the target gaining an attack of opportunity, all participants of the phalanx who can reach the creature attempting to break through while said creature is in any stage of the action gain attacks of opportunity. Any flying or burrowing creature may bypass the formation without provoking attacks of opportunity or having to overrun. Any nonflying and nonburrowing creature who attempts to break through the line from the back must make a similar overrun action, but gain a +5 bonus to the roll. All members of the line lose their dexterity bonus to AC.
In any given group of combatants, any member of that group may initiate a "turtle" maneuver. Any allies who have a shield larger than a buckler may join this maneuver. This counts as a move action for each participant. The participants form a rectangle at least two squares in each direction, holding their shields outward. They may only perform move actions, and only to actually move from one place to another normally. Even this they may only perform as a group, traveling in formation. All members of the group lose their dexterity bonus to AC, but gain quadruple their normal AC from their shields. A burrowing creature may bypass all shield AC by attacking from below.
In any given group of combatants, any member of that group may initiate a surround maneuver. Any allies who have a weapon (natural weapons count) may join this maneuver. The maneuver is otherwise identical to the phalanx maneuver, except that instead of forming a line, they form a circle (the outer spaces of a circular area) and face inward, blocking all inside the circle.
Identical to surround opponent, but the circle faces outward.