I figured I'd mathhammer out how often a Magus will acutally fail at casting
Now I'm using a very basic forumlae that each level takes an equal number of sessions to play to gain enough XP. and that you'll encounter roughly 2 combats per session and for the most part you don't get to rest between encounters in the same session.
and lets say 5 rounds on average per combat so 10 rounds of combat per session
I'll also split fails per level so if you intended not to use spell casting until later you can work out a fail rate closer to your acutal.
Also going to use an agressive amount of spell combat beucase it seems to define the class, using contrips to make up extra rounds.
Although I think most Magus would use at least 1 utility spell per day so -1 spell from each spell level used outside of combat or before combat.
Now going to be maxing out concentration beucase I think any Magus will do the same.
Concentration bonus = Level + combat casting (+4) + caster stat 16 (+3) + trait (+2)
At level 2 when you first get Spell Combat your conentration bonus is +11 or +9 when you apply the peanlty of -2
Ok (remembering 16 gives 1,1,1 bonus spells)
Level 2 (1x 1st level outside of combat)
conc +11
contrips DC17 = 70%
2 x 1st level spells DC19 = 60%
20 rounds of combat = 13.6 sucesful casts = ~6 fails
Level 3 (1x 1st level outside of combat)
conc +12
contrips DC17 = 75%
3 x 1st level spells DC19 = 65%
30 rounds of combat = 21.6 sucesful casts = ~8 fails
Level 4 (1x 1st and 2nd level outside of combat)
conc +13
contrips DC17 = 80%
3 x 1st level spells DC19 = 70%
1 x 2nd level spells DC21 = 60%
40 rounds of combat = 30 sucesful casts = ~10 fails
Level 5 (1x 1st and 2nd level outside of combat)
conc +14
contrips DC17 = 85%
4 x 1st level spells DC19 = 75%
2 x 2nd level spells DC21 = 65%
50 rounds of combat = 38.5 sucesful casts = ~12 fails
Level 6 (1x 1st and 2nd level outside of combat)
conc +15
contrips DC17 = 90%
4 x 1st level spells DC19 = 80%
3 x 2nd level spells DC21 = 70%
60 rounds of combat = 48 sucesful casts = ~12 fails
Level 7 (1x 1st and 2nd level outside of combat)
conc +16
contrips DC17 = 95%
4 x 1st level spells DC19 = 85%
3 x 2nd level spells DC21 = 75%
1 x 3rd level spells DC23 = 65%
70 rounds of combat = 57.4 sucesful casts = ~13 fails
Level 8 DING ! no more -2 (1x 1st,2nd and 3rd level outside of combat)
conc +17
contrips DC17 = 95% (natural 1 is always a fail)
4 x 1st level spells DC17 = 95%
4 x 2nd level spells DC19 = 90%
1 x 3rd level spells DC21 = 80%
80 rounds of combat = 73.2 sucesful casts = ~7 fails
Level 9 (1x 1st,2nd and 3rd level outside of combat)
have more spells than combat rounds now use high levels first
conc +18
contrips DC17 = 95% (natural 1 is always a fail)
5 x 1st level spells DC17 = 95%
4 x 2nd level spells DC19 = 95%
2 x 3rd level spells DC21 = 85%
90 rounds of combat = 83.7 sucesful casts = ~6 fails
Level 10 (1x 1st,2nd and 3rd level outside of combat)
conc +19
contrips DC17 = 95% (natural 1 is always a fail)
5 x 1st level spells DC17 = 95%
4 x 2nd level spells DC19 = 95%
3 x 3rd level spells DC21 = 90%
1 x 4th Level spells DC23 = 80%
100 rounds of combat = 92 sucesful casts = ~8 fails
Level 11 (1x 1st,2nd,3rd and 4th level outside of combat)
conc +20
contrips DC17 = 95% (natural 1 is always a fail)
5 x 1st level spells DC17 = 95%
4 x 2nd level spells DC19 = 95%
4 x 3rd level spells DC21 = 95%
1 x 4th Level spells DC23 = 85%
100 rounds of combat = 94 sucesful casts = ~6 fails
and at this point I think we can say your basically only failing on 1's which is a 5% fail rate
Now if you think thats more combat that you've ever play'd in your life then you'd half the number of combat rounds which would mean your using more of your higher level spells which will push up the fail rate by around 1-5% and delay the platue of 5% fail rate.
as for acutal numbers
For Levels 1 to 7 assuming you play 270 rounds of comabt and spell cast on all those rounds you will have 61 failed spells
I guess what you can reaionble say is that from level 1 to 7 your probably going to fail around casting around 10 spells per level on average if you just spam
if you use it less often you obviously have less fails
if you use lower level spells over higher levels spells your fail rate will pull closer to 5%
regaurdless of what you do you are going to fail casting spells at least 5% of the time over your entire casting career
so I guess the message is don't play Magus if failed casting is going to agrivate you.
its comparable to using buckler and or armor on a mage given a 5-10% arcane spell failure rate at low levels before you can afford mithral
btw the way that concentration arcana that once per day to give a +2 on your check
you'll notice that would acutally pull a top level spell pretty close to 95% during the mid levels and you don't get that many cast per day so maybe not as useless as people first thought it was
Almost exactly the same as my results--I wind up having the Magus buy a +2 Int Headband at level 10 so she can get another bonus 4th-level spell, and this also raises Concentration by exactly 1. Also, 1 is not an automatic failure, which actually eliminates a reasonable number of the lost spells at level 10 and 11.
A natural 1 is always a failure, otherwise you could just skip rolling altogether.
A natural 1 is always a failure, otherwise you could just skip rolling altogether.
Can you give me a quote from the srd or a page number from the Core Rulebook? As far as I know, only saves and attack rolls are auto-fails (they are called out as such). So for a skill check or concentration check, you really don't have to roll if you make it on a 1.
Then what is the purpose of the True Magus 20th level power you no longer need to make concentration checks when performing Spell Combat.
however by your logic at level 17 with a +26 concentration modifier he has this ability already since he cannot fail the DC27 check to cast a 6th level spell. even lower level if he has a +6 headband of INT
you must roll a concentration check but if you can't fail it why roll ?
The designer has even himself stated that he doesn't like the capstone ability as it is, for that reason among others.
Oh my god. It's true, RAW no natural 1 or 20's for anything other than Saves and attacks.
Fortunately I'm usually the GM and can ignore such foolishness.
Then what is the purpose of the True Magus 20th level power you no longer need to make concentration checks when performing Spell Combat.
however by your logic at level 17 with a +26 concentration modifier he has this ability already since he cannot fail the DC27 check to cast a 6th level spell. even lower level if he has a +6 headband of INT
you must roll a concentration check but if you can't fail it why roll ?
You can still fail if the right amount of modifiers are added. Take for example the Disruptive Feat. Having this high of a Concentration modifier just ensures that it won't happen as often.
Oh my god. It's true, RAW no natural 1 or 20's for anything other than Saves and attacks.
Fortunately I'm usually the GM and can ignore such foolishness.
Whereas when I'm the GM, I use telescoping rolls in place of autosuccess or failure (almost always the same, but in edge cases particularly at high levels it makes more sense than the flat 5%). To each our own, eh?