\[ y'(x)=\frac {x \left (-2 x^4+2 x^2 y(x)-x^2+1\right )}{y(x)-x^2} \] ✓ Mathematica : cpu = 0.0268076 (sec), leaf count = 32
\[\left \{\left \{y(x)\to \frac {1}{2} \left (W\left (-e^{c_1+x^4-2 x^2-1}\right )+1\right )+x^2\right \}\right \}\]
✓ Maple : cpu = 0.507 (sec), leaf count = 27
\[ \left \{ y \left ( x \right ) ={x}^{2}+{\frac {1}{2}{\it lambertW} \left ( -2\,{\frac {{{\rm e}^{{x}^{4}}}{\it \_C1}\,{{\rm e}^{-1}}}{ \left ( {{\rm e}^{{x}^{2}}} \right ) ^{2}}} \right ) }+{\frac {1}{2}} \right \} \]