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The tension between the diverging density profiles in Lambda Cold Dark Matter($\Lambda$CDM) simulations and the constant-density inner regions of observedgalaxies is a long-standing challenge known as the `core-cusp' problem. Wedemonstrate that the \texttt{SMUGGLE} galaxy formation model implemented in the\textsc{Arepo} moving mesh code forms constant-density cores in idealized dwarfgalaxies of $M_\star \approx 8 \times 10^7$ M$_{\odot}$ with initially cuspydark matter halos of $M_{200} \approx 10^{10}$ M$_{\odot}$. Identical initialconditions run with the Springel and Hernquist (2003; SH03) feedback modelpreserve cuspiness. Literature on the subject has pointed to the low densitythreshold for star formation, $\rho_\text{th}$, in SH03-like models as anobstacle to baryon-induced core formation. Using a \texttt{SMUGGLE} run withequal $\rho_\text{th}$ to SH03, we demonstrate that core formation can proceedat low density thresholds, indicating that $\rho_\text{th}$ is insufficient onits own to determine whether a galaxy develops a core. We suggest that theability to resolve a multiphase interstellar medium at sufficiently highdensities is a more reliable indicator of core formation than any individualmodel parameter. In \texttt{SMUGGLE}, core formation is accompanied by largedegrees of non-circular motion, with gas rotational velocity profiles thatconsistently fall below the circular velocity $v_\text{circ} = \sqrt{GM/R}$ outto $\sim 2$ kpc. This may artificially mimic larger core sizes when derivedfrom observable quantities compared to the size measured from the dark matterdistribution ($\sim 0.5$ kpc), highlighting the need for careful modeling inthe inner regions of dwarfs to infer the true distribution of dark matter.

Real and counterfeit cores: how feedback expands halos and disrupts tracers of inner gravitational potential in dwarf galaxies