It is a good idea but it works better if you join a high lvl character into the target guild. Because a high level character will lose WAY more money each time he dies than the lower level character. Just join the high lvl char into the target guild. Then unequip all his items to warehouse to avoid losing dura and take him somewhere without any people. Now pk the high level char with a water and revive him and do this over and over and over. Each time he dies the guild fund will go down a decent amount. Your high lvl character will lose a lot of experience too, so it helps if you do it with a warrior that is 100-110. Why? Because at those levels a warrior can level so fast in lab1 with superman and replace the lost experience really quickly.