Write the general term in the expansion of $(x^2 - y)^6$

Question

$\begin{array}{1 1} -\;^6 \large C_r\;x^{12-2r} y^r \\ ^6 \large C_r\;x^{12-2r} y^r \\ -\;^6 \large C_r\;x^{6-r} y^r \\ ^6 \large C_r\;x^{12-2r} y^{6-r} \end{array}$