If you beat halo 3 on legendary do you get the acheivment for beating the campaign on legendary?

basically what it says up there and can you still get all the acheivments if you dont beat it on legendary single player but do on co opIf you beat halo 3 on legendary do you get the acheivment for beating the campaign on legendary?
Yeah, you also get the achievements for Normal and Hard as well.





You still will have to get the skulls (as in pick them up) if you want those achievements.If you beat halo 3 on legendary do you get the acheivment for beating the campaign on legendary?
i think
yep