Long Answer: For the unfamiliar, the Quasi-elemental Planes were the points where the Positive and Negative Energy-Planes met up with the Elemental Planes. This created eight Quasi-Planes with Positive and Air forming lightning. Meanwhile, Negative and Air formed the Vacuum plane. This is an element of the 'Great wheel Cosmology', other Cosmologies such as 5e's recent World Axis Cosmology formed after a stupid wizard caused the scary Spellplague incident. After the Spellplague, these planes melted into the elemental Chaos surrounding the inner planes, while the Positive and Negative Energy planes are shown wrapping around the Outer Planes according to the grouped Plane's alignment.