Old Selective (Feat)

Your allies need not fear friendly fire.

Prerequisites: Level 1

Benefit: When casting a spell, using a magic item, or activating an ability that creates an area-based effect, you may exclude one or more creatures of your choosing from within the affected area. Excluded creatures suffer no effects from the ability, as though they were completely outside the area of effect. With this feat, you can exclude one target from within the ability's area of effect, dealing full effect to all remaining targets in the area. However, for each excluded target after the first, the effect of the spell, item, or ability is reduced. This reduction is equal to 1 point per die rolled per target excluded after the first. All remaining (non-excluded) targets are affected by this reduced amount.

Example 1: A 10th level wizard casts Fireball (Sorcerer/Wizard Spell), but wishes to exclude 3 of their allies. The wizard can exclude the first ally for free, but the other two allies that are being excluded will reduce the dice effect of the fireball by 1 point each per die rolled. Since a fireball cast by a 10th level wizard inflicts 10d6 points of damage, each ally excluded after the first reduces the damage by 10 points (1 per die rolled per ally), for a total of -20 points. Therefore, this fireball will inflict 10d6-20 points of damage on each of the remaining non-excluded targets (you only roll the effect dice once for area of effect abilities, and apply that amount to each target in the area).

Example 2: An 8th level cleric activates their Channel Divinity class feature, and they want to exclude two enemy creatures from the effect. Each creature after the first reduces each die of healing provided by 1 point. So if the cleric would normally heal 5d8+4 with their channel divinity, excluding 2 enemies from the area of effect reduces the healing provided by 5 points (remember that the first excluded target doesn't reduce the effect), becoming 5d8-1.

Note that it is possible to reduce the effect of an ability to the point where it does nothing. If an ability's effect is reduced to a negative number, it is treated as a 0, and has no effect. Any ability that is reduced to 0 or less effect does nothing to the remaining targets, even if it would normally inflict some secondary effect, such as a status condition.

Abilities that do not have an area of effect, or allow the caster to specifically choose which creatures in an area of effect are affected, do not benefit from this feat. In addition, any spells, class features, or magic item effects that specifically state that they cannot be used with Selective do not benefit from this feat (obviously).

Area-of-effect abilities that have a duration greater than instantaneous, such as Fog Cloud, only create gaps for the excluded targets until the start of your next turn, after which, the area of effect fills in all the holes and affects the full area as normal.

If a spell has a damage circle listed, it may still be modified with Mana Burning even if you are excluding targets from the effect, but the final 'damage per character level' is adjusted as described above.

Special: You can take this feat multiple times. Each time you take it after the first, you can exclude 2 more targets within your area of effect abilities before the damage is reduced. (For example, the second time you take it, you can exclude up to 3 targets from your area-based abilities before reducing the effect. The third time you take it, you can exclude up to 5 targets before reducing the effect.)

Special: If your party size contains 8 or more players, you can exclude up to 2 targets from your area-based abilities before reducing their effects, and for each two additional targets you exclude, you reduce the effect by 1 per die of the effect, rounding up if you exclude an odd number of targets (that is, excluding 3 targets is the same as excluding 4 targets). Furthermore, if you choose to take this feat more than once, each time you take it, you can exclude 4 more targets within your area of effect before the effect is reduced (instead of 2; i.e. up to 6 targets if you take it a second time; 10 if you take it a third time). Note that ally NPCs, animal companions, summoned monsters, etc. do not count toward your party's size when determining if you qualify for this effect; only actual player characters in the game, based on the average number of people who actually show up to play (not counting the GM).

Normal: All creatures within the area of effect are affected by the ability.