I've got good news.
With our recent success in clearing out the Xenarth nest (which will hopefully be repopulated soon with more sacrifices), we gained
Bulettes and
Advanced Bulettes. Now, DP has ruled them magical and extraplanar (especially considering their origins of being created with demon blood) and therefore valid sacrifices, but for Day of Blood purposes they would still suffer the -50% modifier for sacrifice value.
However, Day of Blood is not the only sacrifice they qualify for. Due to the demon blood used in their creation, DP has ruled that they will be valid for the purposes of Valyrian Steel, and there are no negative modifiers for low intelligence there. We have 7
Bulettes and 9 Advanced
Bulettes in the
Larder, for a total of 128 HD.
Why does this matter? Because of this:
Before, the spiders were all slotted for Valyrian Steel because the Harbinger, of course, took priority. But now, we have more options thanks to getting more sacrifices, and the spiders can be used to untangle the divine curse without requiring
any research time (though we still have to wait for Yss to wake back up).
Now according to
this post where I already did all the math for sacrifices needed for the Harbinger's Valyrian Steel, we need 285.54 HD (rounded up to 286 HD). With 128 HD coming from the
Bulettes and
Advanced Bulettes, only 158 HD will need to come from the spiders. That can be accomplished by using all 14 of the Huge
FiendishMonstrous Spiders and 3 of the 5 Gargantuan
FiendishMonstrous Spiders, bringing us up to 160 HD.
That leaves 2 Gargantuan
FiendishMonstrous Spiders and 3 Colossal
FiendishMonstrous Spiders. The Colossal spiders are
precisely CR 13. Even if we need a CR 13 sacrifice for each of the spider abominations to be freed from their curse rather than just one for both, we have our options.
I'm not advocating to do this right away, I just wanted to let you guys know that I'd figured out a way to solve this without needing to dedicate research for it. It's not urgent at all, we could sit on this for months and it would be fine.