Abstract: Neutrino astronomy continues to be a rapidly evolving field. In addition to identifying a handful of neutrino sources (NGC 1068, TXS 0506+056, and the Milky Way), the IceCube Neutrino Observatory has identified a diffuse flux of astrophysical neutrinos with unclear origins. Apart from astronomy, IceCube-DeepCore has also proved capable of placing leading constraints on neutrino oscillations. These oscillations may be modified by neutrino-matter interactions beyond the Standard Model - referred to as Non-Standard Interactions (NSI) - making IceCube potentially sensitive to them. In this talk, I will motivate Active Galactic Nuclei - which are promising sites of cosmic-ray acceleration - as significant contributors to the diffuse neutrino flux, and present IceCube-DeepCore’s sensitivity to NSI.