Kamen Rider W DVD: Gaia Memory Library (2010)

Set shortly after Kamen Rider W: Donburi's α/Farewell Beloved Recipe DVD, this video features the content normally found in the Hyper Battle DVD (explaining the powers and weapons of the Kamen Riders), revealed as Philip having come down with temporary amnesia after slipping on a hard-boiled egg and hitting his head.

Unfortunately the movie Kamen Rider W DVD: Gaia Memory Library is not yet available on HBO Max.