It’s a tangler where you bend backward and turn downward while doing tangler.
Start by doing a basic tangler. Lift the tangler up and begin to bend backward.
Turn your torso away from the tangler but keep your hands parallel to each other.
Bring the tangler downward. Turn your body around the tangler more.
Keep those hands parallel.
As much as you can, try to move the body around the tangler. As you get deep into the turn, your arms are going to be at a very awkward angle. Get the yoyo through that repetition then you can straighten everything out with one quick spin.
Get your hands re-situated, then dismount.
Tricks to know before Reverse Fountain Tangler: