Backcrosses

Backcrosses are crossing throws made behind the back, where the object comes forward on the same side of the body where it will be caught.

Tips

Avoid leaning back, sticking your elbows out, or twisting your body to the side.
Make sure that none of your backcrosses or normal throws are lower than your basic pattern height, and that you're not waiting too long to start a throw, so you will have enough time to make a proper throw before you have to catch another object.
If you're throwing clubs out too wide, you need to hold on to them longer. If they're hitting you in the head, you're holding on too long.

Backcross world records with publicly available video evidence:

5 ball backcrosses: 2 minutes and 44 seconds by Adolfo Almonacid in 2019 (video)
6 ball backcrosses: 71 catches by Ty Tojo in 2012 (video)
7 ball backcrosses: 125 catches by Ty Tojo in 2013 (video)
8 ball backcrosses: 8 catches by Ty Tojo in 2013 (video)
9 ball backcrosses: 9 catches by Ty Tojo in 2015 (video)

Unverified claims:

3 ring backcrosses: 183 catches by Matan Presberg in 2017 (video)
5 ring backcrosses: 35 catches by Delaney Bayles in 2017 (video)
7 ring backcrosses: 7 catches by Pavel Evsukevich in 2012 (video, video) and Laido Dittmar in 2014 (video)

Unverified claims:

3 club backcrosses: 16 minutes and 38 seconds by Chris Fowler in 2007 (video)
5 club backcrosses: 203 catches by Kristian Wanvik in 2015 (video)
6 club backcrosses: 12 catches by Wes Peden in 2006 (video)
7 club backcrosses: 7 catches by Anthony Gatto in 2007 (video at 5:15), Vova Galchenko in 2007 (video), David Ferman in 2012 (video), Jack Denger in 2013 (video), Wes Peden in 2015 (video), Kento Tanioka in 2017 (video), Anderson da Silva in 2019 (video), and Spencer Androli in 2020 (video)

Records with insufficient video evidence:

Unverified claims:

Scissors - a variation of the wimpy pattern where either every throw is a backcross,^(video) or only one hand throws a backcross at a time, with a different hand doing the backcross in each pair of throws (sometimes called half scissors or alternating scissors).^{(ball video, club video)}
Backselves - a non-crossing version of backcrosses. An object thrown as a backself from the right hand is thrown behind the back, comes forward on the left side of the head, and is caught in the right hand.
Shoulder throws
Body throws
Reverse backcrosses
Backcross rolls
Contortion
Blind behind the back
Behind the back looking
Behind the back madness