Guns N' Roses Return with 'Welcome to the Jungle' and Axl's Still Got It!

This is gonna blow your mind ... and ears.

If you thought Guns N' Roses was coming back at less than full force ... listen to Axl Rose launch into "Welcome to the Jungle."

Friday night's Troubador show was the first time the classic lineup of Axl, Slash, and Duff McKagan had played together since 1993, and by all accounts they killed it as they ripped through 17 songs.

Closer? "Paradise City" ... of course.