Roadhog's Chain Hook ability can be used in a specific spot on Lijiang Tower that guarantees kills on players. The Chain Hook ability is one that most heroes who have either 200 or less health points fear, given that as of now, successfully landing the hook and then dealing an auto-attack will take out at least 195 health points, if not more should a player land a critical hit.
In maps like Ilios and Lijiang Tower now, the hook has the ability to kill enemies through environmental kills: "dragging" them to the edge of a well in Ilios, or the unique spot a streamer found while live on Twitch.
An Overwatch streamer named Gibba went outside of the main point and into a balcony, from which they could see the enemy team and their spawn. Despite there being metal structures, he aimed the hook in between them to pull an enemy McCree forward. Because it was over the edge of the balcony, it resulted in an environmental kill (and a brief stun from the McCree.) Gibba's Twitch clip can be seen here.
It is assumed that because the player aimed the hook through a narrow space between the metal structures of the balcony, it is doable multiple times. Though it is worthy to note that the Chain Hook is notoriously known for having had multiple bugs (and changes) in the past. Whether this is a bug that will be fixed in a patch, or a new spot for players to kill immobile enemies, remains to be seen.