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Ko [26] and Bruschi [11] independently showed that, in some relativized world, PSPACE (in fact, ⊕P) contains a set that is immune to the polynomial hierarchy (PH). In this paper, we study and settle the question of relativized separations with immunity for PH and the counting classes PP, $\mathrm{C}=\mathrm{P}$, and ⊕P in all possible pairwise combinations. Our main result is that there is an oracle relative to which $\mathrm{C}=\mathrm{P}$ contains a set that is immune BPP. In particular, this ${\mathrm{C}=\mathrm{P}}^A$ set is immune to PH and to ⊕P. Strengthening...