Trying to find this book again

[demeaninglion6]

I cannot remember the name of the book nor the author and this is basically my last resort, ive been trying to find it on and off since middle school and have been unsuccessful.
a kid is out with his parents (either at a dig site with his dad or at a picnic with him) and stumbles upon an arrowhead leftover from a war. the kid touches it and pricks his finger on it while also absorbing a sliver of the arrowhead and gains the power to absorb powers from other people (I can't remember if he has to kill them or not), he ends up falling in love with a snake demon lady? but she never reciprocates. and her dad was also the one the war was about. at the end of the book the evil guy goes back in time and changes history and that's how the book ends.

Comments

[full_metal_ox]

Happy 2026; I see your account was newly created, perhaps for the purpose of using this comm; welcome to Dreamwidth!

That sounds a bit like this Reddit querent’s summary, which a commenter identified as the Ash Mistry series: https://www.reddit.com/r/whatsthatbook/comments/1eupkzg/ya_fiction_kid_gets_a_sliver_of_a_divine_indian/ The “demon lady” might be the Goddess Kali, whose agent Ash becomes.

(A magic arrowhead that confers power and a timeline reset are also elements of JoJo’s Bizarre Adventure Part 6: Stone Ocean, but those are the only areas of overlap I can think of.)