Kippenhahn plots showing the structure of a 110 M_⊙ star evolved with enhanced mixing (left), with MLT++ (middle) and with enhanced mass loss (right). The Y-axis represents the mass coordinate inside the star while the X-axis represents the time remaining in the life of the star before the end of the run is reached. Green, purple and red hatching mark the regions with convection, overshooting and semiconvective mixing, respectively. In all three panels, the helium core boundary is the outermost location where the hydrogen mass fraction is < 0.01, while the helium mass fraction is ≥0.01, and is represented by the blue dashed line. Similarly, the carbon core boundary is defined as the outermost location where the hydrogen and helium mass fraction are < 0.01 while the carbon mass fraction is ≥0.01. It is represented as the red dashed line.