[Crow]

MS Paint:

1. Create a copy of the sprite, still on the same canvas though.
2. Enlarge the copy to 140% (using both horizontal and vertical stretching at the same time in the stretch & skew menu), so it has the correct size in the end.
3. Apply and reselect. Open the stretch & skew menu again and skew horizontally by 45 degrees. Apply.
4. Reselect and open up the menu again and skew vertically by -26 degrees (we separate these two steps since it usually gives better results). Apply.
5. Reselect one last time, open up the menu once again and stretch horizontally to 50%.
6. Clean up.