I'm looking for a Japanese feature film, I think it's from the Super Troopers series, and the thing I remember most about it is that there are a lot of villains in it, all of them appearing in sequenc

I'm looking for a Japanese feature film, I think it's from the Super Troopers series, and the thing I remember most about it is that there are a lot of villains in it, all of them appearing in sequence. Can't think of any that have the exact same plot, and can't find any in the Battle Team series that meets all the criteria you mentioned. In terms of the entire team being defeated and one of them having his mask broken, 2001's Hyakuman Battle Team #30 fits the bill the best. Also, the cadre-level monsters in the Beast Battle Team aren't traditionally organized, but rather consist of a male and a female lower-level cadre assisting the higher-level cadre, with the next cadre appearing after one of the higher-level cadres dies, which is more in line with what you're describing as a sequential appearance.

Also, I don't know what era your childhood was.

According to Japanese special effects enthusiasts, other examples of mask-breaking are as follows:

Birdman Battle Team, 50th episode

1997 Electromagnetic Battle Team, 8th episode

1997 Electromagnetic Battle Team, 30th episode

1999 Rescue Battle Team, 3rd episode

2000 Mirai Battle Team, 28th episode

2001 Beast Battle Team 30

2007 Beast Fist Battle Team 45

2008 Inferno Battle Team Final

2012 Extraordinarily Fateful Battle Team 14

2012 Extraordinarily Fateful Battle Team Final