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tokens: of the most massive stars to the core results in a runaway stellar collision (Portegies Zwart et al. 2004 ; van der Marel 2004 , p. 37). This collision produces a seed BH of several hundred to several thousand solar masses (Katz et al. 2015 ). 3. Over the next several billion years the halo continues to accrete gas, feeding additional star formation and the central BH. During this era, feedback from bursty star formation precludes the formation of a significant bulge (Guedes et al. 2011 ; Governato et al. 2010 ). 4. Between 5 and 10 Gyr ago, the dwarf falls into Centaurus A. This allows enough time for its gas, dark matter, and outer stars to be completely stripped (Smith et al. 2013 , 2015 ), therefore the DSCs would not be hosted in the surviving subhalos at z = 0. At z = 0, the only remaining sign of the lost dwarf is the remnant cusp of stars surrounding its central SMBH. Excepting its dynamics and metallicity, the surviving stellar cusp resembles a GC. Since these systems resemble GCs photometrically and structurally, it is only possible to disentangle their origin as lost dwarf galaxies through the dynamic signatures of their central BHs and the following observational criteria. Chemical composition : if the DSCs formed as dwarf galaxies their residual stellar populations should accordingly have dwarf galaxy-like chemical abundances; namely, a significantly elevated metallicity dex, a measurable metallicity spread (), and a higher ratio than expected for their present stellar mass on the –luminosity relation of stellar systems (e.g., Thomas et al. 2005 ; Smith et al. 2009 ). In addition, they should be above expectations from the L –[Fe/H] relation for systems with . From the selective enrichment by core-collapse supernovae we would also expect enhanced ratios of light elements (CNO) to iron, as well as a significant variance in iron-peak elements. X-ray flux : while the central BH is likely now quiescent, low-level accretion (∼10 −8 Eddington) is possible via AGB (asymptotic giant branch) winds and planetary nebulae. At Centaurus A’s distance, even these low accretion rates would be detectable by Chandra or XMM for the expected central BH masses. 6. SUMMARY AND CONCLUSIONS We have used a new set of high-resolution simulations of an isolated Centaurus A analog to investigate possible formation models for the DSCs found in T15 . We assume that the DSCs formed within dark matter halos before determining which Centaurus A subhalos at z = 0 have the highest probability of being DSC progenitors. We find that DSCs likely formed in dark matter halos that virialized at high redshift with . Since dark matter halos grow in mass in isolation, we assume that any DSC progenitor had . However, no dark matter profile associated with the Centaurus A system, whether for the subhalos at z = 0, z peak , or high redshift (e.g., z = 9.3), has a high enough central density to account for the dynamical mass derived for the DSCs. Even the densest DM halos fall