The planet series are series of variants off a base puzzle. So far there has been a planet series of the Crazy 3x3s, Crazy megaminxes, Crazy tetrahedra, Crazy pentahedra and Bermuda cubes (did I miss anything?).
The 'crazy' puzzles have circles on their faces. The pieces inside the circle may or may not turn when the face is turned. Different planets are different configurations of the two circle types around the puzzle (the tetrahedra also have non-circle faces).




The Bermuda cubes are 3x3x3 cubes with some faces having a triangle as a centerpiece instead of a square (and the faces may be fishered or not). Different planets are different configurations of triangle-faces and normal faces.
This thread is dedicated to solving the circle puzzles.
This thread is dedicated to bermuda cubes.
In
this thread there is a link to a simulator with loads of these puzzles.
You can buy the puzzles from, for example
HK Now Store or
mf8. With the circle cubes and megaminxes, if you want the whole set, you need to buy just two puzzles (so that you have equal amonuts of both face types) and you can exchange centers and get all the other versions. With the crazy pentahedra, you can flip an internal piece that determined if a side face is type 0 or 1. With the other puzzles, you may want to ask around what is recommended. I hear that the Uranus Tet is devilishly hard.
Here is a demo of the crazy 3x3.
Here is Rox's crazy megaminx demo.
Here is a demo of a crazy tetrahedron.
This is pretty much the only video that I found of the crazy pentahedrs that didn't involve solving :3
Here is a video of the bermuda cubes.
I hope this helped!