Bloodline XP math

[rrwoods]

While perusing optimization showcase #2, I notice that the build says to take three bloodline levels at ECL 1, and that you should get to level 2 at 4k XP and 3 at 6k. I'm new to bloodlines, but this confuses me. With one class level and three bloodline levels, wouldn't you hit 2 at 10k? What am I missing?

[GilesTheCleric]

You can take 3 levels of bloodline between class levels 1 and 2. Each level of bloodline costs 1k xp, for a total of 3k. Add 3k to the xp needed for level 2 and each class level after.

[rrwoods]

Why does each bloodline level "cost" 1k XP?

Wait, I think I get it -- when you take a bloodline level, since your character level doesn't increase, the next XP increment required to level is the same as the one you just went through, rather than 1k higher?

So, say you take two class levels. When you get to 3,000 XP, you opt to take a bloodline level. Your next level comes at 5,000?

[GilesTheCleric]

Bloodlines both count as levels and also don't (essentially whichever is better for the player for each instance; there's no other apparent logic to it). So you gain skill max ranks, but don't gain HD. You progress CL, but don't get spells or spell slots. Save DCs based on character/ class level continue to scale, but you never actually have those class levels. It's pretty silly.

So yes, when you add bloodline levels, they don't count as levels for xp requirements and thus will continue to cost the same if you take several of them in succession between the same two levels (1 and 2 are typically chosen since that's when they're cheapest).

I'm reading over it again to see what the xp cost for each bloodline level is, and I'm pretty sure that it's the delta between your current level and the next level. So, if you took one after level 2, it would cost 2k xp per level of bloodline. If you only took one level, you would now need 5k xp total to level to 3. If you took all three, then level 3 would arrive once your total xp count hits 9k. So yes, you've understood it correctly (I think; bloodlines are pretty poorly written the whole way through).