Tokusatsu (特撮?), sometimes shortened to Toku, is a Japanese term that applies to any live-action film or television drama that usually features superheroes and makes considerable use of special effects (tokusatsu literally translates as "special filming" in Japanese).
The Kamen Rider Series has crossed over with other tokusatsu series on occasion. Kamen Rider 1 teamed up with Ultraman in Ultraman vs. Kamen Rider (1993) and four heroes from Shotaro Ishinomori's other works (Kikaider, Kikaider 01, Inazuman, and Zubat) made a cameo in OOO, Den-O, All Riders: Let's Go Kamen Riders (2011). Most of all, Kamen Rider has a strong relationship with Super Sentai, they have made up the Super Hero Time block on TV Asahi for over a decade now and are often seen together, but have only had two official crossovers, with shorter crossovers seen in TV specials.