More Attacks in a Standard Action (3.5e Variant Rule)
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More Attacks in a Standard Action
Combat actions in stock 3.5e do little to distinguish or give additional value to feats and class abilities that grant extra attacks to a PCs attacks per round, when the PC is only making a standard action. Likewise, monsters with multiple primary attack parts gain little benefit when there is only a standard action in a round to attack. As written, these additional attacks are worth no more than the iterative attacks gained from increasing BAB. So in order to make them different and more notable, revise the Combat Actions rules as follows:
As a standard action, you may make your primary attack, and any additional attacks you are granted by virtue of an affect or feat that do not suffer at least a -5 attack penalty. For example, a monk using Flurry of Blows or a character using the Two-Weapon Fighting feat can make two attacks - one for each hand (Someone without the Two-Weapon feat would not gain this second attack in a standard action, as they suffer at least a -8 penalty on the offhand). An archer with the Rapid Shot feat can loose two arrows in a single standard action. The Haste spell grants an additional attack at the PCs full BAB, so again this is included in a standard attack.
Any iterative attacks gained through high BAB require a full attack action. This includes additional offhand attacks gained with Improved and Greater Two-Weapon Fighting (since they suffer at least a -5 penalty), and effects which grant you more attacks by virtue of giving you a higher BAB or decreasing the BAB interval for additional attacks - such as Transformation.
For creatures with natural weapons, such creature, as a standard action, can make one attack with each natural weapon that is considered primary. A full attack action is necessary to attack with any remaining secondary attack parts. So for example, a hydra is allowed to make one attack for each of its heads in a standard action. A dragon would be able to use both fore claws and a bite as a standard action - while any additional attacks with the tail, wings, or rear claws would require a full round attack. A creature with no primary attack weapons may use one secondary natural weapon in a standard attack - though this attack is still made at -5 to its attack roll.
A creature with the Multiattack feat gets to attack with all of its secondary natural weapons in a standard attack. A creature with the Multiweapon Fighting feat gets to use all of its weapon-bearing attacks in a standard attack. This in both cases is consistent with the rule of any attack that doesn't suffer a -5 or greater penalty gets to go off in a standard attack action.
This has the effect of making combat grittier and resolve faster. High CR, dangerous creatures become more so against higher level players, and feats become more evenly distributed in value for the entire length of a character's progression.