Let me preface with, this multi class choice is 90% for flavor and RP as are most of the decisions made with this character, it’s not the most optimized and it isn’t meant to be and my DM is fine with the third party class.
My character has 11 levels in Oracle - Life
I’m going to be adding in 5 levels of Omdura but am gaining my first one soon after a series of one shots for each player’s character in our group.
My question is in the case of spell casting what level should be used? Unlike mixing Arcane/Divine, there are many spells that fall on both spell lists (both Inquisitor and Cleric/Oracle) and as an Omdura you can choose whether it’s from the cleric or inquisitor list. Barbed Chains is a prime example and the spell that brought up the discussion between my DM and myself, both are 1st level on the cleric and inquisitor spell list with the below text:
“You summon a chain from another realm, causing it to burst out from the ground and strike a target within the spell’s range. You can have the chain either make a melee attack (dealing 1d6 points of slashing damage) or attempt a trip combat maneuver against the target. The chain uses your base attack bonus plus your key spellcasting ability score modifier as its attack bonus and combat maneuver bonus. On a successful hit or combat maneuver check, the target must attempt a Will save. If it fails its save, the creature is shaken for 1d4 rounds. You summon one additional chain every 3 levels after 1st, for a total of two chains at 4th level, three at 7th level, and a maximum of four at 10th level. Multiple chains can attack the same target but the shaken effect doesn’t stack.“
Because I’m picking up this spell thanks to the 1 level in Omdura, would I treat it as only having 1 level of spellcasting, or would I use my full 12 levels of casting as it’s on both lists and the verbiage is ”every X levels after 1st?”
Would I be using my full base attack bonus or just what I get from Omdura as well?
Lastly, and not pertinent to this particular spell, for example 1d6 per level of damage, would that be full caster level total or would it be based on the class I used to get it? (and this is only for spells that appear on both lists, I’d only get access to inquisitor spells through Omdura so it it’s ONLY an inquisitor so I would assume that would only use my Omdura level)
Oracle spells cast using oracle spell slots use oracle levels, omurda spells use omurda levels.
They don't stack, combine, or even look at each other. They are 2 separate and independent things.
They are also considered 2 Separate things for spells known. Knowing a cure as an omurda won't let you cast it with oracle spell slots and vice versa.
the classes don't combine in accumulative manner for caster level and such. Essentialy the PC is a Life Oracle 11 & Omdura 5 in one package.
You might try going the Mystic Theurge route but that's 3 & 3 then MysThg 10 = 16 levels. That way you'll be high(er) level caster. Usually it's Wizard and Cleric.
Another option is Bloatmage.
You should check out Magical Knack trait.
Saying this character is not optimized may be the understatement of the year. A lot of people would consider the character to be purposely nerfed. You are giving up 6th, 7th and 8th level spells and 5 caster levels for a few low-level spells and a few low-level abilities.
From the looks of it you are trying to go for an Oradin build but it really does not work that well. I would suggest just taking 2 levels of paladin instead. That way you still get 6th and 7th level spells and get better saving throws.
All class features from different classes are separate unless otherwise stated. Hitpoints, Base Attack bonus, Skill points and Saves will all stack, but as a general rule everything else is separate.
However the Oracle's curse actually does level with your levels in other classes, because it has specific language saying so:
Oracle's Curse (Ex): Each oracle is cursed, but this curse comes with a benefit as well as a hindrance. This choice is made at 1st level, and once made, it cannot be changed. The oracle's curse cannot be removed or dispelled without the aid of a deity. An oracle's curse is based on her oracle level plus one for every two levels or Hit Dice other than oracle. Each oracle must choose a single curse.
So your Oracle-11/Omdura-5 will have the beneifts of a 13th level Oracle's Curse (11 from Oracle, 5÷2 rounding down = 2 from Omdura). This won't affect your mysteries or other class features, but if you have a Curse that gives you a bonus equal to half your level, or if your Curse has an offensive ability that scales with level then this can help it stay relevant. It also means that you would get the level 15 benefit of the Curse at Oracle-13/Omdura-5, rather than waiting until Oracle-15.