A standout bit of info here is the Bloody Sigil helping with this. Ho-le-wow. Because this whole thing technically breaks JJ HARD. Sounds like double or even more (or possibly a lot more) than what I'm used to seeing.
It might not be too murderous on a bloodmage because it drains blackspace (fat chace, JJ Bloodmage is silly even without it), but JJ halflings could cheeze so much health out of this it's not even funny.
JJ Halfling Priest with Cauldron, anyone?