Not sure if this has already been covered. I did a search, but didn't see anything (didn't do an exhaustive search though). Also not sure if this is the appropriate location to post this clarification/question/observation.
Magus Special Ability:
Spell Combat (Ex): At 1st level, a magus learns to cast spells and wield his weapons at the same time. This functions much like two-weapon fighting, but the off-hand weapon is a spell that is being cast. To use this ability, the magus must have one hand free (even if the spell being cast does not have somatic components), while wielding a light or one-handed melee weapon in the other hand. As a full-round action, he can make all of his attacks with his melee weapon at a –2 penalty and can also cast any spell from the magus spell list with a casting time of 1 standard action (any attack roll made as part of this spell also takes this penalty). If he casts this spell defensively, he can decide to take an additional penalty on his attack rolls, up to his Intelligence bonus, and add the same amount as a circumstance bonus on his concentration check. If the check fails, the spell is wasted, but the attacks still take the penalty. A magus can choose to cast the spell first or make the weapon attacks first, but if he has more than one attack, he cannot cast the spell between weapon attacks.
-So you're taking a -2 penalty on an attack, but also casting in the same round to make it function like two-weapon fighting.
-Casting while in a threatened hex (which is the only time this ability would be used) provokes an AoO. It is quasi offset by giving the option to cast defensively increasing the penalty to the attack of the physical weapon.-The concentration check made to cast the spell only comes into play if said character takes damage from the AoO, and would be d20 + caster level + int mod (plus bonus if you happened to cast defensibly) vs 10 + spell level + damage taken.
Given that concentration is no longer a skill, and therefore no reliable way to increase odds of success of achieving concentration as levels progress, why is this a core component of this class? At low levels, this might seem like a good gamble to take, but after about 5th level - you're going to be hit and the DC will be impossible to beat unless you roll a natural 20 for automatic success. The only way I can see this being remotely effective and possible, is with the feats combat casting and mobility.
Am I wrong on my assessment, or is there something else I'm not seeing to make this a worth while class feature?
The description specifically states wielding a light or one-handed melee weapon, but it doesn't say said melee weapon can't be used as ranged i.e. dagger or spear and 5 ft away so you aren't within something's threatened square to provoke the AoO. Is this an acceptable interpretation?
Since Magii are 6/9 casters, the spell levels don't advance too fast for their concentration checks. Second, his spell combat ability lets him take additional attack penalties in exchange for a bonus to concetration. Thirdly YOu can always cast, move towards a foe w/ a 5 fter, and then spellstrike & normal attack.
Also, concentration is essentially as skill that all classes are gent full ranks in and use their appropriate modifier vs their con in 3.5.
For example, at 5th level, casting a 1st level spell: the dc is 17 for concetrating defensively. Your bonus is 5(Caster level) + 4 Int(most casters have that much at this level) + 1d20. You'll succeed on an 8, so you have 60% chance of success. You can sacrifice more of your attack to really nail that hit home if need be, which isn't bad since magii enchance their weapons.
-So you're taking a -2 penalty on an attack, but also casting in the same round to make it function like two-weapon fighting.
-Casting while in a threatened hex (which is the only time this ability would be used) provokes an AoO. It is quasi offset by giving the option to cast defensively increasing the penalty to the attack of the physical weapon.
-The concentration check made to cast the spell only comes into play if said character takes damage from the AoO, and would be d20 + caster level + int mod (plus bonus if you happened to cast defensibly) vs 10 + spell level + damage taken.Am I wrong on my assessment, or is there something else I'm not seeing to make this a worth while class feature?
You don't make a concentration roll due to taking damage. You make a concentration roll to cast defensively.
That makes it 15+spell lvl*2. That is 17 for a spell like shocking grasp, which should give you a 50% chance around lvl 3-4. You can take combat casting for a nice bonus. If you start taking a penalty to attack and bonus to concentrate, you can pretty quickly almost auto-succeed on your casting defensively rolls.Alternatively, you can make your attacks, 5-ft step away, and cast the spell. No provoking, no casting defensively.
Or, if not adjacent at first, cast a spell, 5-ft step in and attack.
You are confusing 2 things.
If you cast a spell in a threatening square and DONT cast defensively the opponent who is threatening you gets one AOO and IF he hits the DC will be higher with the amount of damage he did.
BUT
If you cast defensively he does NOT get an AOO although if you don’t make you concentration check to cast defensively your spell fizzles.
To cast defensively you add your INT modifier with your class level and a D20 so at level 1 considering you have 16 Int it would be
1d20+1+3
And the DC would be twice the spell lvl +15 so let’s say you want to shocking grasp it would be DC 17 needing to roll 13
if you would be using spell combat you can take up to -3 on attack rolls to add +3 to the concentration check so you would have a 50% chance to succeed at lvl 1 you only have a very limited times of shocking grasp so don’t worry about it and cast it when not threatened!
What you will be casting or should is arcane mark witch is a DC15
Also combat casting feat gives you +4 to cast defensively
A magus also gets bonuses to cast defensively and an INT of 18 is not strange.