First of all, there's this online web novel called Worm: https://parahumans.wordpress.com Then, this: https://www.goodreads.com/book/show/25895524-red-sister I bought the epub not too long ago, and although sharing it with you may be considered a violation of PCC terms, but as they say, sharing is caring: https://ufile.io/7mtff
Anyway, Mark Lawrence works are mainly based on grimdark, so give his other books a try as well, especially Prince of Thorns. The series is quite dark, so be prepared.