<< Graphics`ImplicitPlot`

ImplicitPlot[
      x^3 - 3*x*y + y^3 == 0, {x, -2, 2}, {y, -2, 
        2}]

ImplicitPlot[
      x^3 - 3*x*y + y^3 == -0.1, {x, -2, 2}, {y, -2, 
        2}]

ImplicitPlot[
      x^3 - 3*x*y + y^3 == 0.1, {x, -2, 2}, {y, -2, 
        2}]