Octahedron
Octahedron[] represents a regular octahedron centered at the origin with unit edge length.
Octahedron[l] represents an octahedron with edge length l.
Octahedron[{θ,ϕ},…] represents an octahedron rotated by an angle θ with respect to the z axis and angle ϕ with respect to the y axis.
Octahedron[{x,y,z},…] represents an octahedron centered at {x,y,z}.
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