What is the test for instructing a sua sponte on a self-defense defense?

Generally, "[a] party is not entitled to an instruction on a theory for which there is no supporting evidence. [Citation.]" (People v. Memro (1995) 11 Cal.4th 786, 868.)⁵ Thus, "[a] trial court is required to instruct sua sponte on any defense, including self-defense, only when there is substantial evidence supporting the defense, and the defendant is either relying on the defense or the defense is not inconsistent with the defendant's theory of the case. [Citation.]" (People v. Villanueva (2008) 169 Cal.App.4th 41, 49; see also People v. Miceli (2002) 104 Cal.App.4th 256, 267.)