We study certain deformations of four-dimensional N=2 superconformal field theories (SCFTs) with non-abelian flavor symmetry which preserve an N=1 supersymmetry. The deformation is described by adding an N=1 chiral multiplet transforming in the adjoint representation of the flavor symmetry with a superpotential coupling, and giving a nilpotent vacuum expectation value to the chiral multiplet which breaks the flavor symmetry. This triggers a renormalization group flow to an infrared SCFT. Remarkably, we find that classes of theories flow to enhanced N=2 superconformal fixed points in the infrared under the deformation. For instance, the deformations of N=2 supersymmetric SU(N) QCD with 2N flavors and Sp(N) QCD with 2N+2 flavors flows to the (A_1, A_{2N-1}) and (A_1, A_{2N}) Argyres-Douglas theories respectively. From these “Lagrangian descriptions,” we compute the full superconformal indices of the (A_1,A_n) theories and find perfect agreements with the previous results in some limits. Other examples of the infrared supersymmetry enhancement include generalized Argyres-Douglas theories and rank-one SCFTs with non-abelian flavor symmetries. This talk is based on the collaborations with Jaewon Song and on the papers arXiv:1606.05632 and 1607.04281.