I'm getting ready to start on PoD after completing the previous three games. What a ride! I had a dwarf fighter/thief for the first three games. I want to make a dual class fighter-thief (9/? or 13/?) to replace my dwarf for my PoD run. I'm trying to figure out what would be the appropriate ball park level split for my new character using the same accumulated experience from my dwarf. I know that's somewhat cheating. I just want to start my new character off exactly where my old one left off. Does that make sense? I currently have another dual class character in the party, a fighter-mage, at 9/15. Everyone else is single class with roughly 2.6 million xp.

Instead of dualing at level 9 you might as well keep your multiclass, hitpoints will be the only difference on the long run.

Since you're planning to use an editor consider simply raising HP by 4 and the multiclass fighter levels to 13 to remove the level cap, your character won't be stronger than a late dualclass.

Creating a new fighter and dualing to thief at level 15 will also work without using any editor, the fast levelling thief class might even overtake the imported characters' final classes, if you edit in the XP from the previous game dualing at level 17 is the better choice, you party starts with a lot of extra XP so you can afford a long dualing period for one character.

Thanks for the advice K. I guess I figured I would dual at level 13 so I could get 2 APR. So I basically just used the XP of my dual class fighter-mage for a reference and I my 'new' thief came out to be a 13th level fighter/ 14 thief. I'm not sure if that's right. What would be there reason for waiting till level 17 to dual?

What you get at level 17 (compared to level 13):
+4 to hit
+4 HP (+8 if changing to mage)

The +4 HP is rather miniscule, so it depends on whether you want to be more useful now, or want to be more powerful later.

The question becomes, then, is the +4 bonus needed to reliably hit late-game enemies?

Well he's wielding a +5 Longsword from SotSB so he has a -2 THACO. Is that not enough? Also is using the XP my dual mage has a good reference for determining my experience?

Technically he gets 12 HP for waiting 3 fighter levels. But yeah, it's mostly about the +4 to hit--THAC0 maxes out (mins out, really) at 17th level for fighters.

Given how quickly thieves gain levels it's probably better to wait. One of the things is that there are parts of the game where you have to give up all items for a bit so it's better to get your THAC0 down a bit by advancing thief levels before you go there.

Yes, but you miss out on the 8 (or 4 in the case of dualing to mage) HP, that you would have gained for those 3 levels, so you only get a net gain of 4 (or 8 for mage) HP.

Ah thanks. I should have caught that. Getting lazy...