Dual class fighter constitution bonus

Pingwin

I've just rolled up an illusionist character with 17 CON as I'm planning on dual classing him to a fighter at the earliest opportunity to create a wand using uber fighter.
Just a quick question about his constitution bonus - obviously he will be getting a +2 hp bonus on his 2 illusionist levels, and +3 on the fighter levels from level 3 onwards, but once he's become a fighter, does the +3 bonus retrospectively get applied to the illusionist hitpoints and so give him 2 extra hp?

ilduderino

I’m afraid not but he will get it for the fighter levels that are above the mage ones

Danacm

As i know she will gain the above 16 con bonus only to fighter levels.

Btw why illusionist for basic class ? Stronger spook, blind ?

Pingwin

Once he has dual classed, he'll be wearing heavy armour all the time so spell slots are limited to spells that have some use outside of combat, which usually will be Identify.
Making him a specialist mage to begin with just means he'll usually have 3 Identify spells per day instead of 2 at the cost of not being able to use scrolls from opposing schools, and Illusionists fare a bit better than other specialists in terms of missing out on the fewest important spells. Also the second ability score requirement for a specialist mage made getting a good stat roll slightly less tedious.

Very_BigSword

I have been thinking about this build recently and came to the same conclusions as you. As icing on the cake you could play a low rep run and get 6 necromancy spells anyway for Bhaalspawn abilities. For a fighter though I might find DUHM to be more useful than vampiric touch, maybe one of each.

Wand and scroll use is 100% worth the sacrifice of 16 max HP. And every wand, protection scroll that you find can be identified on the spot for immediate availability to use.

Grond0

You could start a character with 18 constitution, so potentially you lose the benefits of going to 19 with the tome in BGEE. That would give a maximum loss of 6 per level + 5 con bonus - or 22 if dualling at 2nd level. The 16 @Very_BigSword refers to takes account of the bonus from a summoned familiar in BGEE (unless you're lawful evil as imps have slightly fewer HPs).

However, if you're playing BG2EE as well, you can summon a new familiar there - meaning your net loss is only 4 if you do that immediately (and if you're not playing with maximum HPs the effect will be roughly neutral). If you wait to summon a second familiar until ToB you can even get a net gain of at least 8.

Danacm

I used to had an invoker/ fighter dual but never finished that run in bg2. Btw the fire wand was very brutal with the -2 penalty bonus from school specialization. The scorcher kill many stronger foes alone.

Pingwin

I'm now busy taking a different character through BG2 but, I'm having second thoughts that when I get round to trying this, I should go for a regular mage -> fighter dual instead of Illusionist. Two spell slots for Identify will be plenty anyway and he will get to use fun scrolls like Vampiric Touch and Horror.