Reign and the others tried their best to catch up to any groups that were nearby in order to eliminate them before they were able to get to the wall. The total number of demons was larger compared to the number of players, which meant that they needed to try their best in order to lower the number of demons that would arrive at the wall.
They had the advantage when it came to the Tier III combatants thanks to the monster army, not to mention that the monsters didn't fear death and would simply charge and kill anything in front of them during battle, but the demons didn't fear death either, which meant that the players would be heavily pressed during the battle.