In one chapter Gai used Hiroudora at base form and pushed back Madara Susano and broke it(the mokuton grip on Killer Bee was loosened after the attack). Hiroudora is a 7th gate technique this shows that Gai can use moves from the gates at base form on any other gates. So he can use moves like the Night Gai/Moth nnot in 8th gate without dying but the power gets decreased since he is not in 8th gate. But remember he pushed back Susano in base form and was weakened U_U. Just want to show something I found I think it's pretty cool.