|Patryn of Elvenshae|
First, the odd rules language:
Pool Strike (Su): A magus with this magus arcana can expend 1 point from his arcane pool to charge his hand with elemental power as a standard action. He can make a melee touch attack as a free action as part of activating this ability. If the attack hits, it releases the charge and deals 1d6 points of energy damage of a type of his choosing, either acid, cold, electricity, or fire. He can use this ability with the spellstrike class feature. If he misses with this attack, he can hold the charge for up to 1 minute before it dissipates. At 3rd level, and every three levels thereafter, the amount of damage dealt by this attack increases by 1d6.
So, your first opportunity to pick up a Magus Arcana is 3rd-level.
So, assuming you pick this up as early as possible, it starts at 1d6, and, since you're 3rd-level, increases by 1d6, to 2d6, meaning that the real baseline of the ability is 2d6, not 1d6.
Wouldn't clearer text be, "... realeases the charge and deals 2d6 points of energy damage ... At 6th level, and every three levels thereafter, the amount ... increases by 1d6" ?
And now the question:
How does this ability interact with the Spellstrike class feature, if you've already used that ability to channel a touch attack through your weapon?
Assume you cast Shocking Grasp, and elect to channel it through your weapon. You miss on the ensuing attack, and hold the charge. On your next turn, you elect to use Pool Strike, and also channel it through your weapon via Spellstrike. Do you deal [weapon damage] + [Shocking Grasp] + [Pool Strike]?
The issue is complicated by the rules on holding the charge:
Touch Spells and Holding the Charge
In most cases, if you don't discharge a touch spell on the round you cast it, you can hold the charge (postpone the discharge of the spell) indefinitely. You can make touch attacks round after round until the spell is discharged. If you cast another spell, the touch spell dissipates.
Specifically, the original touch spell (Shocking Grasp) dissipates "if you cast another spell."
Using Pool Strike is not casting another spell; moreover, it isn't a spell-like ability, either; it's supernatural. Accordingly, a close reading would indicate that nothing untoward happens when you try to mix a touch spell and a Pool Strike.
Is that working as intended?
I actually really like the idea of being able to add it to touch spells. Think about it. By level 20 you're doing what, 5d6 with it? I've been doing that with Shocking Grasp since level 5. But adding extra dice of damage onto a spell? Suddenly it becomes much better for burst damage purposes. Plus, it makes the Magus even better at touch spells.
It's something I'm going to look into on a spell by spell basis, and I'm one of those people that would rather say NO now, then add abilities to the character later, than say YES now, and have to take away later.
The speciics elude me at the moment, but I remember coming up with something using this ability when I first saw the magus, that seemed to do quite a bit of damage in one shot. If memory serves it was well balanced in my opinion with players in mind, as you had to use a lot of actions to get everything aligned, or you could only do it once per day...something like that...then I realized a magus NPC I was working on would essentialy erase a single NPC on the first round of combat, and then be able to whoop a fair ammount of booty afterward. I don't go out of my way to kill players (generally the opposite), but if the players have access to a solid tactic, NPCs who would be just as capeable of utilizing it will do so...