Rotor / Propeller
Rotor is well described by:
Reverse Bird > Inside Star > Goofy Bird > Inside Star > Reverse Bird.
Propeller is well described by:
Reverse Bird > Inside Star > Goofy Bird > Inside Star > Reverse Bird.
I consider them to be the same machine.
There is a YouTube video 2011/08/25 where Graeme and Lux perform Rotor in two versions (version two is basically what the community refers to as Flatspins). In the video, Rotor is performed with Reverse Hand-to-Hand grip.
Apparently Aaron Lind and Matt Giordano created the same machine many years ago, using Hand-to-Hand grip and naming it Propeller.
I didn't know which was created first, so I asked Aaron Lind, and he confirmed they did it in 2012.
I therefore prefer to refer to it as Rotor, even though I learnt it as Propeller and I'm more used to knowing it as Propeller.
Flatspin is a different version of the same machine, performed with streamlined hand grips and pops so that it can be performed rather fast.
A video of Propeller:
Propeller with Lara:
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