How does the Brewkeeper prestige class's Helpful Homebrew metamagic effect interact with the cleric's prepared spells?

Question

I have recently came across the Brewkeeper prestige class and I fell in love with it. The interactions it has with spells and potions is amazing for late game, especially when you have potions left over from lower levels; but one thing bothers me.

I know metamagic increases the level of the spell being cast but with brewkeeper you can add a metamagic effect onto a spell as you cast it. Cleric cast using prepared spells, so I want to know what happens when you add a metamagic effect onto it with the brewkeeper's helpful homebrew ability:

Helpful Homebrew (Su): At 2nd level and every 2 class levels thereafter, a brewkeeper can select one metamagic feat from the list in the following paragraph. She can spend points from her brew reservoir as a swift action to add a metamagic effect to a spell as she casts it, an extract as she drinks it, or a draught as she creates it. She does not need to meet the feat’s prerequisites in order to select the effect. Using this ability costs a number of brew points equal to the metamagic feat’s level increase (minimum 1).

Does it use up a spell slot of a higher level? If so, wouldn't that break the aspect of clerics needing to prepare the spell beforehand? For instance, if you prepare a use of a level 2 spell and augment it to level 3 with Helpful Homebrew metamagic, would that result in using a 3rd level spell slot while keeping all your level 2 spell slots free to take other spells?

Answer 1

I would rule that it does not alter the prepared spell slot expended, nor does it increase the casting time or level of a spell cast spontaneously.

The reason for this is that you end up with larger rule issues if you interpret this ability the other way around.

Lets take the simplest case; A spontaneous caster uses this ability. Normally when a spontaneous caster uses metamagic, they increase the casting time of that spell. If they had already spent their move action, they cannot take longer. Yet they are casting a spell, and so qualify for using this ability.

Similarly, for any caster it lacks the restriction that you must be able to cast the higher level spell normally. The trigger is as you cast. So if I cast cure wounds from my highest level spell slot, I qualify for using this ability.

The ability also lacks the wording found in spontaneous abilities for prepared casters such as cleric's spontaneous harm/heal, or druid's spontaneous Summon Nature's Ally:

The Cleric can 'lose' any prepared spell ... in order to cast any cure spell of the same spell level or lower

This text is aimed at fixing any issues with combining spontaneous with prepared.

However, as a counter argument, the text does lack the specific wording found in Metamagic Rods;

.... allowing the user to apply metamagic effects to spells as they are cast. This does not change the spell slot of the altered spell.

There is an element of interpretation here. Is the second sentence of the text I quoted for Metamagic Rods, an explanation of what happens when you add metamagic 'as you cast', or is it a change on how it would normally work?

So in summary: Either this does increase the level and/or casting time, in which case it lacks wording restricting when you can do it, and no clear instructions for working out how it functions.

Or it lacks wording saying that it doesn't increase the level.

The second option is far, far simpler. Hence my ruling.

I also don't think it is overpowered. The metamagic you can do this with is limited to certain choices which while good, critically do not include Quicken.