The Powerpuff Girls (lost pilot of Cartoon Network animated series reboot; 2016)
The 2016 Powerpuff Girls is an animated reboot based of the original 1998 series.
An original pilot has been made, and so far has only been discussed in an interview of EG Daily (the original voice of Buttercup) and Otakus and Geeks.
According to Daily, her, Tara Strong and Cathy Cavadini did actually record a pilot episode of the series, with different showrunners. But after Nick Jennings and Bob Boyle replaced the unknown show runner, they decided to replace them with different lead characters.
The article is available here: http://www.otakusandgeeks.com/articles/2015/10/23/interview-with-eg-daily/author