Total HD keep 2 highest + HD keep 2 lowest

Hi there everyone! I'm fiddling with my homebrew of the Black Hack, and I want to limit the amount of HP to the sum of 4 HD of the total (10HD et.c) and I want to have multi-classing that penalize dabbling in magic if you are a Barbarian, et.c. eg. A level 5 character can have 3 level in Wizard (d4) and 2 levels in Barbarian (d12), and would be given less HP on avarage when HP is rerolled (when resting) because of the d4's. I want the 2 lowest rolled dice and 2 highest rolled dice to be picked. Obviously this will only work you have HD over the amount of 5. /roll [[@{selected|hitDie}kh2]]+[[@{selected|hitDie}kl2]] This gives you the total HD + the total HD, instead of the keep 2 highest + keep 2 lowest. Why doesn't it work? Thank you for any help! /FireVisor

I dont think there's a way to do what you want. Your current macro will roll the HD once, select the 2 highest dice from them, then roll the hit dice again, and select the two lowest from that second roll. I think the only way a free user can do what you want is something like this: /roll @{selected|hitDie}sd This will roll the dice, sorting them from high to low, and you can pick the two dice at the start and the two dice at the end and manually add them together.

is there a statistical difference?

I guess not, you could do it as two separate rolls, but I doubt that would fly at many non-virtual game tables.