Madonna Plays Celeb Truth or Dare to Announce World Tour

If you want Madonna's truth -- that she's going on tour again -- you're first gonna have to sit through several racy dares with her celeb friends ... so, apologies to Diplo's balls!!!

Yep, that's just a taste of what went down in Madonna's 'Celebration Tour' announcement video ... which features Madge playing Truth or Dare with the likes of Jack Black, Lil Wayne, Amy Schumer, Eric Andre, Judd Apatow, Bob the Drag Queen, Meg Stalter and yes ... Diplo.

This is the only place you could see Diplo dip his junk in a margarita and then chug it ... followed by Madonna jamming her tongue down Jack Black's throat ... before she strikes an R-rated ménage à trois pose with Weezy and Jack!!!

That's just a sample of what went down at Madonna's twisted game night -- which was a fun tip of the hat to her 1991 concert film, "Truth or Dare."

The tour announcement came when Amy dared Madonna to "do a world tour and play your greatest muthaf***ing hits." The iconic singer responds, "Four decades? All those songs?" -- which gets the whole room singing their fave Madonna classics.

The 35-city world tour will kick off in North America ... first show is July 15 in Vancouver, BC ... and the last is December 1 in Amsterdam -- and yes, she'll be singing all THOSE songs.

In her media announcement, Madonna added, "I am excited to explore as many songs as possible in hopes to give my fans the show they have been waiting for."