What are some skills that can proc in spriggan form?

[Oni]

I know of Thorn Totems and Eterra's Blessing, but are there more?

[king_casian]

From a quick check on lastepochtools, these seem to also work:
Storm Totems from (Unique relic) Stormcarved Testament. (I'm still hunting for this one.)
Maelstrom from (Shaman) Swirling Maelstrom, (Spriggan) Glacial Grove and (Spriggan) Spirit Vortex and several Uniques.
Before trying to answer this question, because I was curious myself, for my Arctic Arbor build, I had never used that website, so there may well be more I didn't quite know how to find easily. (and it's near midnight here, with work early in the morning.)
Just thought I'd share those results, at least.

[Oni]

lastepochtools is way better than maxroll in my opinion.