Ryze Afks as a bot in custom game

I was practicing a bit and i had a ryze in the enemy team (as a bot). he was playing till around level 12 and he had a catalyst, sorcerer shoes and a tear. after that he went afk after i killed him and stayd there just using his q abilitie!i placed a ward near him and walked towards him too but he didnt seem to attack. just pressing his q.