Ranma ½: Battle ga Ippai 29-nin no Korinai Yatsura
English name: Ranma ½: Huge Battle! 29 Unteachable Fools
Genres: Comedy, Slice of Life
Type: OVA, Episodes: 1
Aired: Mar 3, 1995
Studio: Kitty Film Mitaka Studio
Source: Unknown
Rating: PG-13 - Teens 13 or older
Synopsis:
This special, known in Japan as "Batoru Kaiibai 29 Hitou Korinai Yatsura," was available through the Kitty Animation Circle making it a difficult item to come by. It contained clips from twenty-nine of Ranma's most memorable opponents from the television series. 

(Source: furinkan.com/ranma/anime/specials.html)