A lance? I'm pretty sure that they find ways to counter it. they could build traps, dig pits that horses could fall into or make a lance of their own. A lance is basically a thick giant spear after all.
Problem with pit traps is that they take time and effort to make. Maybe if it was a siege or they were protecting a town.
The Chinese did have lances, but they were alot like the ones Europeans first used, which were long spears.
European lances were more for shock strikes, made for hitting an enemy hard, with very narrow points.
Another thing people mistake is the the lances broke when they hit someone, tournament ones did that so people were less likely to be killed.
I don't know. That giant hammer looks like it can do some damage. Even if it does not kill it can defiantly maim to the point of being taken out of battle.
Problem is that, that hammer can be heavy, but its reach is pretty short compared to a lance, and most knights carried kite shaped shields, that protected both men and the horse.