Talk given as part of European XFEL Users' Meeting 2018. Topics include: X-ray techniques for biological structure determination at XFELs; fluctuation x-ray scattering; single-particle structure recovery from fluctuation x-ray scattering; SPI experiments on aerosolized virus particles at the AMO instrument, LCLS; diffraction before destruction; size distribution histograms for RDV and PR772; generalization of SAXS, higher-order SAXS; extended set of cross-correlations; 2D correlation maps; experimental 2D correlation maps for RDV and PR772; model-based structure analysis; sensitivity of cross-correlations to structure variation; conventional iterative phase retrieval; multitiered iterative phasing (MTIP); MTIP reconstructions of RDV and PR772; beyond single particle imaging, multiple-particle FXS.