As late as possible, of course. Well, not more than 25 fighter levels, because you do want to complete the dual before the experience cap.
The tradeoff is how much of the kensai bonuses you get against how long it takes to bring the class fully on line. You've only asked about the former.
When I've done the dual, I've usually gone for level 13. Full warrior APR, good saves, and I can use scroll XP to clear up virtually all of the downtime if I want to.
As late as possible, of course. Well, not more than 25 fighter levels, because you do want to complete the dual before the experience cap.
The tradeoff is how much of the kensai bonuses you get against how long it takes to bring the class fully on line. You've only asked about the former.
When I've done the dual, I've usually gone for level 13. Full warrior APR, good saves, and I can use scroll XP to clear up virtually all of the downtime if I want to.
Oh sorry I should have mentioned that I don't care at all about how long the down time is for the dual classing process to complete so long as it is the optimal one.
(supplemental question) If I grandmaster in the katana when I back stab as a thief will it utilize the proficiency I got as a fighter (assuming its a thief allowed weapon) or not?
If you don't care at all about the downtime - then yes, as late as possible. You get your combat ability from the fighter (kensai) class levels, after all. Level 25 is the maximum that still lets you complete the dual before 8 million XP, though you might want to dial that back to level 24 since all you get from level 25 is a fighter HLA, and you give up a thief HLA for it.
Once you complete the dual, you will get all benefits of your fighter class levels, including any weapons you specialized in or more. In a backstab, essentially all sources of damage except strength get multiplied. For example, a kensai 13/thief 14+ with 19 strength, Celestial Fury, katana grandmastery, and no other relevant gear, backstabs for (1d10 + 3 (enchantment) + 4 (kensai) + 5 (grandmaster))*5 + 7 (strength) = 72-117 physical damage.
There's no question that given the Kensai's level-based bonuses, more Kensai levels means more damage bonuses. But that comes at a cost. If you dual very late, then you'll spend only a small fraction of the game as a dual-class and the rest as two separate single classes. If you dual very early, you spend more time as a proper dual but you lose some damage bonuses.
Where you draw the line as to how much to frontload or shift to the back half of the game is up to you. For some people, the end of ToB is all that matters; for others, the SoA midgame might be where they feel they want to pop the most; or it could be anywhere in between. Lastly, whether/how you've modded your game and what the rest of your party looks like can also be a concern.
What is "optimal" there is up to subjective preference. But there's two key breakpoints most people consider:
Lvl 9 - this will give decent Kensai bonuses, full fighter hit dice, +0.5 APR, and Grand Mastery. It recovers the dual quite quickly, and so you spend most of the game actually having two classes.
Lvl 13 - this gives more bonuses, and another +0.5 APR on top of the lvl 9 dual. It takes significantly more time to recover the original class, though, as experience requirements peak after lvl 9 (all of lvl 1 to 9 takes as much total XP as just going from lvl 9 to lvl 10). You will spend a lot of time as single-class Kensai and single-class Thief, respectively, but you'll recover early enough to play a good chunk of SoA as a dual.
Any duals later than that risk not recovering at all in SoA, meaning you spend a majority of your time playing single-class characters.
To me personally as a powergamer, there's almost no question that lvl 9 is the way to go. Yes you lose out on some bonuses, but in the grand scheme of things it's more valuable to have SoA midgame power as that's where you tend to struggle with lack of powerful gear etc. Once you acquire all the high-end items, you're already so strong that a few additional damage barely makes a dent. But dualing at 13 is a reasonable compromise if you don't mind the delay or feel confident that SoA isn't a big deal. I wouldn't dual any later than that, as the return on investment just gets worse and worse after 13.
Essentially, if you dual at Level 13 the final character will have an extra 5 THAC0 and 0.5 APR. The trade-off is you only spend the back third of Shadows of Amn as a Kensai/Thief. If you dualed at Level 9 you could spend all of Shadows of Amn (and the end of Siege of Dragonspear if you're playing) as a Kensai/Thief.
Based on what you've said I would think you'd want to go with 13.
i had a play through where i went kensai 18 then dualled over to thief just so i could use the holy avenger, ended up pretty good
You don't need to dual at 18 for that, though In fact you'll get it even faster if you dual earlier, since for most people reaching 18 Kensai/24 Thief is going to take FAR longer than acquiring Carsomyr...
If I'm playing a thief with extra fighting ability, then I like to dual at 7. You can make it out of Chateau Irenicus with both classes activated and ready to plunder Amn.
i had a play through where i went kensai 18 then dualled over to thief just so i could use the holy avenger, ended up pretty good
You don't need to dual at 18 for that, though In fact you'll get it even faster if you dual earlier, since for most people reaching 18 Kensai/24 Thief is going to take FAR longer than acquiring Carsomyr...
i belive my reasoning was optimal damage output while still being actually able to use the class for some of ToB, i hit level 18 in chapter 5 of SoA and i hit level 19 in watcher's keep after i defeated yaga shura, so i was able to actually use it for at least half of ToB, plus with more fighter levels more HP, and i believe the thief side still hit level 34 or 35 at level cap.
If I'm playing a thief with extra fighting ability, then I like to dual at 7. You can make it out of Chateau Irenicus with both classes activated and ready to plunder Amn.
For BG2, I think that's a waste of some decent benefits from getting to 9. The extra XP to regain 9 over 7 is fairly small in BG2 terms, definitely worth the investment IMO.
There's no question that given the Kensai's level-based bonuses, more Kensai levels means more damage bonuses. But that comes at a cost. If you dual very late, then you'll spend only a small fraction of the game as a dual-class and the rest as two separate single classes. If you dual very early, you spend more time as a proper dual but you lose some damage bonuses.
Where you draw the line as to how much to frontload or shift to the back half of the game is up to you. For some people, the end of ToB is all that matters; for others, the SoA midgame might be where they feel they want to pop the most; or it could be anywhere in between. Lastly, whether/how you've modded your game and what the rest of your party looks like can also be a concern.
What is "optimal" there is up to subjective preference. But there's two key breakpoints most people consider:
Lvl 9 - this will give decent Kensai bonuses, full fighter hit dice, +0.5 APR, and Grand Mastery. It recovers the dual quite quickly, and so you spend most of the game actually having two classes.
Lvl 13 - this gives more bonuses, and another +0.5 APR on top of the lvl 9 dual. It takes significantly more time to recover the original class, though, as experience requirements peak after lvl 9 (all of lvl 1 to 9 takes as much total XP as just going from lvl 9 to lvl 10). You will spend a lot of time as single-class Kensai and single-class Thief, respectively, but you'll recover early enough to play a good chunk of SoA as a dual.
Any duals later than that risk not recovering at all in SoA, meaning you spend a majority of your time playing single-class characters.
To me personally as a powergamer, there's almost no question that lvl 9 is the way to go. Yes you lose out on some bonuses, but in the grand scheme of things it's more valuable to have SoA midgame power as that's where you tend to struggle with lack of powerful gear etc. Once you acquire all the high-end items, you're already so strong that a few additional damage barely makes a dent. But dualing at 13 is a reasonable compromise if you don't mind the delay or feel confident that SoA isn't a big deal. I wouldn't dual any later than that, as the return on investment just gets worse and worse after 13.
Comments
The tradeoff is how much of the kensai bonuses you get against how long it takes to bring the class fully on line. You've only asked about the former.
When I've done the dual, I've usually gone for level 13. Full warrior APR, good saves, and I can use scroll XP to clear up virtually all of the downtime if I want to.
Oh sorry I should have mentioned that I don't care at all about how long the down time is for the dual classing process to complete so long as it is the optimal one.
(supplemental question) If I grandmaster in the katana when I back stab as a thief will it utilize the proficiency I got as a fighter (assuming its a thief allowed weapon) or not?
Once you complete the dual, you will get all benefits of your fighter class levels, including any weapons you specialized in or more. In a backstab, essentially all sources of damage except strength get multiplied. For example, a kensai 13/thief 14+ with 19 strength, Celestial Fury, katana grandmastery, and no other relevant gear, backstabs for (1d10 + 3 (enchantment) + 4 (kensai) + 5 (grandmaster))*5 + 7 (strength) = 72-117 physical damage.
Where you draw the line as to how much to frontload or shift to the back half of the game is up to you. For some people, the end of ToB is all that matters; for others, the SoA midgame might be where they feel they want to pop the most; or it could be anywhere in between. Lastly, whether/how you've modded your game and what the rest of your party looks like can also be a concern.
What is "optimal" there is up to subjective preference. But there's two key breakpoints most people consider:
Lvl 9 - this will give decent Kensai bonuses, full fighter hit dice, +0.5 APR, and Grand Mastery. It recovers the dual quite quickly, and so you spend most of the game actually having two classes.
Lvl 13 - this gives more bonuses, and another +0.5 APR on top of the lvl 9 dual. It takes significantly more time to recover the original class, though, as experience requirements peak after lvl 9 (all of lvl 1 to 9 takes as much total XP as just going from lvl 9 to lvl 10). You will spend a lot of time as single-class Kensai and single-class Thief, respectively, but you'll recover early enough to play a good chunk of SoA as a dual.
Any duals later than that risk not recovering at all in SoA, meaning you spend a majority of your time playing single-class characters.
To me personally as a powergamer, there's almost no question that lvl 9 is the way to go. Yes you lose out on some bonuses, but in the grand scheme of things it's more valuable to have SoA midgame power as that's where you tend to struggle with lack of powerful gear etc. Once you acquire all the high-end items, you're already so strong that a few additional damage barely makes a dent. But dualing at 13 is a reasonable compromise if you don't mind the delay or feel confident that SoA isn't a big deal. I wouldn't dual any later than that, as the return on investment just gets worse and worse after 13.
Kensai (9)>Thief
BG/TotSC - Kensai (161K)
SoD - Kensai (89K), Thief (160K), Kensai/Thief (90K)
SoA - Kensai/Thief (2.45m+)
ToB - Kensai/Thief
Kensai (13)>Thief
BG/TotSC - Kensai (161K)
SOD - Kensai (339K)
SoA - Kensai (750K), Thief (880K), Kensai/Thief (820K+)
ToB - Kensai/Thief
Essentially, if you dual at Level 13 the final character will have an extra 5 THAC0 and 0.5 APR. The trade-off is you only spend the back third of Shadows of Amn as a Kensai/Thief. If you dualed at Level 9 you could spend all of Shadows of Amn (and the end of Siege of Dragonspear if you're playing) as a Kensai/Thief.
Based on what you've said I would think you'd want to go with 13.
i belive my reasoning was optimal damage output while still being actually able to use the class for some of ToB, i hit level 18 in chapter 5 of SoA and i hit level 19 in watcher's keep after i defeated yaga shura, so i was able to actually use it for at least half of ToB, plus with more fighter levels more HP, and i believe the thief side still hit level 34 or 35 at level cap.
Thank you, most insightful.