@thethainUA Ranger, Halfling, Bear companion, If I am riding him, can he still attack, (I feel the rules say no, but my heart says yes) yes, he totally can if you don't try to control him. But he's your buddy so he'll do what you want. #wotcstaff
— (((Mike Mearls))) (@mikemearls) October 15, 2016
So how would this affect a rider with a more intelligent mount than a horse?