The Kannon's Heart Dungeon had many humanoid monsterlings, and as soon as players entered the dungeon, they would see five military bases before them. The humanoid monsterlings surged out of these bases endlessly, like a tide.
Just like the previous three Party-level Dungeons, players would not receive any EXP from the monsterlings here until they defeated the final boss.
However, Li Yi knew that their killing monsterlings here would still amount to something in the end. When they completed the dungeon, all of the EXP from the previous battles would be added to the final tally and awarded to the players accordingly.
The Kannon's Heart Instance Dungeon's endless stream of soldiers and EXP had always been a bug, and in the early days of the dungeon's operation, many players used this bug to farm levels. In the end, the Pantheon developers settled the matter by having the soldiers award no EXP from then on, but they did not punish any of the players.