A few years ago, BadAxe Games put out a supplement called Trailblazer. I recently discovered it while wandering down an internet hole that started at a post on the Pathfinder Google+ community. The folks at Bad Axe apparently had the same thought as I did because they created a great set of rules called Combat Reactions.
A combat reaction allows you to take certain actions even when it isn't your turn; attacks of opportunity are a classic example of a combat reaction. Trailblazer pulls actions like Aid Another into the same family as AoO, allowing characters to use their often-wasted AoO to promote teamwork on the field.
Around the same time I discovered Trailblazer, I read an intriguing post from gamer and blogger Brandes Stoddard at Harbinger of Doom on what he calls 'Giving Ground,' a technique that fits beautifully under the combat reaction umbrella.
I've adopted both of these ideas, tweaked them a bit and will be playtesting them in my Jade Regent game soon.
Combat reactions allow you to perform special actions any time during a round, not only on your own turn. Combat reactions are considered immediate actions and you may take 1 combat reaction per round at 1st level. You gain an additional combat reaction when your Base Attack Bonus (BAB) reaches +6, +11, and +16. The Combat Reflexes feat gives you a starting number of combat reactions equal to your Dexterity score.
If you are threatening an opponent that is engaging an ally in melee combat, you can assist your ally as a combat reaction. Multiple allies can aid the same target. Aid ally combat reaction bonuses stack with each other, but not with other circumstance bonuses.
Aid Attack: You must announce your intention to aid your ally before the attack roll is made. Your ally then gains a +2 circumstance bonus to that attack.
Aid Defense: You must announce your intention to aid your ally's defense before your opponent rolls their attack. Your ally gains a +2 circumstance bonus to their AC (or Defense Score if using the Armor as DR rules) against the opponent's attack.
Full Round Aid Ally: Instead of using combat reactions to help your party, you may instead declare a full round aid ally. Full round aid ally may only be declared on your turn and you may take no other action (other than a 5ft step). When using a full round aid attack, you grant your ally a +4 circumstance to attack rolls against the threatened target until the beginning of your next turn. When using a full round aid defense, you grant your ally a +4 circumstance to AC (or DS) until the beginning of your next turn against attacks from the threatened opponent only.
Unlike aid ally combat reactions, full round aid ally bonuses do not stack.
Attack of Opportunity
AoO works as written in the core rules, though Trailblazer does encourage one small change. I don't plan on using this rule at this time, but I can understand the reasoning behind it.
Engaging: Engaging with an opponent does not provoke an attack of opportunity. Moving into an opponent's threatened area engages you with that opponent and therefor does not provoke an attack of opportunity.
This rule prevents the often bizarre movement we see at the table, with people zig-zagging everywhere and taking several minutes to figure out how to avoid AoO when closing on their target.
You may temporarily increase your damage reduction against a single melee attack from an opponent no more than one size category larger than you, by blocking the attack with a weapon or shield. You must be aware of the attack, not be flat-footed, and must announce your intention to block before your opponent rolls their attack. While blocking, you gain DR equal to 1/2 BAB (rounded down; min 0) against the attack. DR gained from the block combat reaction stacks with other forms of DR, including armor if the Armor as DR rules are being used.
Normal Weapon/Shield: DR/magic
Magic Weapon/Shield: DR/adamantine
Adamantine Weapon/Shield: DR/-
Shield Blocking: When using a shield other than a buckler, you may choose to block a single ranged attack instead of a melee attack. You may also add the shield's AC bonus (not including enhancement bonus) to the DR of the attack.
If blocking DR is bypassed by the appropriate attack, the weapon or shield used to block the attack gains the broken condition. If a broken weapon or shield used to block is bypassed by the appropriate attack, it is destroyed.
Characters with the Improved Unarmed Combat feat may attempt to block melee attacks from normal weapons only. Monks with the ki pool class feature, creatures with DR, or creatures with similar abilities treat unarmed blocks as DR/magic or DR/adamantine as applicable.
You may increase your defense against a single melee or ranged attack. You must be aware of the attack, not be flat-footed, and must announce your intention to dodge before your opponent rolls their attack. While dodging, you gain a bonus to your AC (or DS) equal to 1/2 your BAB (rounded down; min 1) against that attack.
You may reduce some of the damage taken by a melee attack by retreating from your opponent. When successfully hit by a melee attack, you may use a combat reaction to move 5ft away from your opponent. After completing the move, you may reduce the damage taken by 1/2 your BAB (rounded down; min 1). If using the Wounds and Vitality rules, this reduction in damage only applies to VPs.
- Your 5ft step must be taken away from your opponent.
- Giving ground provokes attacks of opportunity from opponents other than the attacker who triggered the giving ground action.
- As a combat reaction, your opponent may take a 5ft step into a space adjacent to you after your move is completed.
- You may not move 5ft into difficult terrain, into a space occupied by an ally, or any other illegal space unless you have a feat or other circumstance that allows such movement (such as your ally being Tiny).
- If your 5ft move is unable to be completed for any reason, the damage is not reduced.