Large AdS$_6$ black holes from CFT$_5$

We study supersymmetric AdS$_6$ black holes at large angular momenta, from the index of 5d SCFTs on $S^4\times\mathbb{R}$ in the large $N$ and Cardy limit. Our examples are the strong coupling limits of 5d gauge theories on the D4-D8-O8 system. The large $N$ free energy scales like $N^{5/2}$, statistically accounting for the entropy of large black holes in AdS$_6$. Instanton solitons play subtle roles to realize these deconfined degrees of freedom.