Confusion on bonuses per levels

[zarconww]

There seems to be some BIG confusion on bonuses per levels. Not the
just the one that say " +1 per level". All the abilities, spells, feats,
schools and domains, that say you get a +1 per every 2, 3, 4 levels of the caster and so forth. Some GM's I have played in games with read it
literally, such as with Force Missile , you get 1D4 +1 at first level
+1 per every 2 levels . Then you would not get the next +1 until level
4. Then some GM's read it like the spell Magic Missile where you get the +1 for every 2 levels that the character has gained past the level that
he/she aquired the ability. Making it at 3rd, 5th, and so forth.
The latter makes sense when you read some descriptions that say when the
max is reached.
I believe that you get the base at the level you pick up the ability and
then add the bonus at each step of character level gain.
But this would make a Type-O in the Magus archetype of Blackblade. The
Magus aquires the Blackblade at level 3 and the Int starts at 10 but
then it says it gets a +1 to INT per every 2 levels of the Magus ( 3rd,
5th, and so forth. Wouldnt it be the +1 at 5th , 7th and so forth?
I am playing a level 3 Wizard / Evoker and have that problem.

[PsychoDan]

Well Force Missile, at least, explicitly says 1/2 your wizard level. That always rounds down, and has a minimum of +1, so you wouldn't get to +2 until 4th level.

In general, abilities that count the levels after you acquire them will state that explicitly. Look at the way Sneak Attack is worded, for example: "This extra damage is 1d6 at 1st level, and increases by 1d6 every two rogue levels thereafter." Or Inspire Greatness: "For every three levels a bard attains beyond 9th, he can target one additional ally while using this performance (up to a maximum of four at 18th level)."

If something simply says to add your class level, or 1/2 your class level or anything like that, count your entire class level.

[zarconww]

Well the point I was trying to make was, I think different DEVs worked
on different parts of the rules and they used different terminology in
the descriptions. I just think that it needs to be uniform .

[Jacob Saltband]

How do you read +1 per 2 class levels?

[Sean K Reynolds]

From the intro to the Class chapter, under Multiclassing:
Note that there are a number of effects and prerequisites that rely on a character's level or Hit Dice. Such effects are always based on the total number of levels or Hit Dice a character possesses, not just those from one class. The exception to this is class abilities, most of which are based on the total number of class levels that a character possesses of that particular class.

From the intro to the Spells chapter, under Caster Level:
Caster Level: A spell's power often depends on caster level, which is defined as the caster's class level for the purpose of casting a particular spell. A creature with no classes has a caster level equal to its Hit Dice unless otherwise specified. The word “level” in the short descriptions that follow always refers to caster level.