Continual Fire (3.5e Other)
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Certain weapons target an area instead of a single creature, affecting anything in either a cone- or line-shaped burst. Using such a weapon in combat requires a standard action. Continual fire is when the effect of such a weapon is sustained for one or more rounds. If a weapon is capable of using continual fire, it is listed in that weapon's equipment statistics block.
Continual Fire in Combat: Laying down continual fire requires a full-round action. Continual fire allows you to use the applicable weapon to make two attacks in one round. The first attack is resolved at the start of your turn, and the second attack is declared at the end of your turn.
A creature that starts its turn within the effect area of the second attack must make a Reflex save against a DC of 10 + ½ your base attack bonus + your Dexterity modifier. If it succeeds, it is allowed to immediately expend a move action in order to either escape the weapon's blast zone or find cover. If it doesn't or if neither are possible, or if a creature purposely enters the affected area, it receives the effects of the second attack.
If the weapon normally allows a saving throw, so do all attacks within a continual fire.
Ammunition: When weapons work with fuel or ammunition, one round of continual fire requires double the amount of a normal attack.