Chinese wall

Chinese wall is a running and tagging game for larger groups. The playing field must be bigger the larger the group is.

Equipment
It would be great if ropes or mats could be used to mark the wall, but if nothing is available, you can also play without that.

Rules
The (roughly rectangular) playing field is split into two parts of roughly the same size. One player (the catcher) is standing on the border between those two parts, he is representing the chinese wall. After a starting signal, all the players run from one end of the playing field to the other, having to pass the line (the wall). The catcher may tag those players, but he may move only along the wall. Any player he can tag also becomes part of the wall, and can help him to tag in the next round.

Players may only move forwards or sidewards, but not backward to evade the catcher.

Chinesische Mauer