Benefit: You can modify a spell that deals acid, cold, electricity, or fire damage to deal damage through high-pressure water instead. The spell gains the water descriptor, and you can either replace the spell’s normal damage with bludgeoning damage or split the spell’s damage so that half is bludgeoning and half is of its normal type. Creatures with damage reduction apply their damage reduction to bludgeoning damage from a benthic spell, but the spell counts as bludgeoning and magic for the purposes of bypassing damage reduction.
A benthic spell uses up a spell slot one level higher than the spell’s actual level.
So, I have a Shaman running through the Strange Aeons campaign (now level 6) that has chosen the Waves wandering Spirit, and the Crashing Waves Hex. His main spirit is Nature (and has the witch doctor archetype) but that is unimportant. What I want to do is use Benthic spell (and Magical Lineage/Wayang Spellhunter) to maximize my ability to force Fortitiude saves or be prone with EVERY elemental spell I cast, while combining it with other unpleasant effects.
I have chose Pale Flames (a better Produce Flame) and Call Lightning as my chosen spells to reduce metamagic costs with Benthic Spell. I am open to alternate options. I want to come up with interesting descriptions of what these spells would look like when used to deal bludgeoning damage, and gaining the water descriptor. I know the feat was surely intended to make elemental damage spells work better underwater, but it is not limited to underwater.
The only thing that I can think of that seems plausible (or believable) across the spectrum of all the spells I will eventually use with the feat is that the addition of the water descriptor “supercharges” the spell into a form that is more “real” than the target it is hitting, more “solid” in reality. So, instead of taking the elemental damage, the energy just bludgeons the target as the energy refuses to interact with it (or partially interacts with it, should we only want to convert half the damage to bludgeoning).
As a side note, I do not plan on being a blaster. My character is designed to be able to shift into multiple different roles as the need calls for it, though his primary tactic is to “buff” his wife (Bloodrager) with Protective Luck (Hex) and Chant to keep it up, while using his other standard actions to drop another Protective Luck on another, or follow up with another “buff” to his wife. He uses Shield Other on her as well (though earlier in the day) and serves as a backup HP batter for her. It is only after that, that he begins to consider using his other spells. Since he has the Healing Token spell, he only has to use immediate actions to heal his allies in combat (though this uses spells or channels as normal).
If it comes down to it, he can enter Melee with his Morningstar and Barbarian rage (VMC Barbarian). Since I plan on almost never making a full attack, I will (maybe) be picking up Vital Strike and Improved Vital Strike eventually, though the (GM approved) Split Hex feat takes precedence. How effective my spells turn out to be may sway me towards other feats.
Thanks for reading. Looking forward to suggestions. (Oh, he has a Protector Familiar to serve as his own HP battery.)