There should be town attacks in this game. When monsters invade a certain town and the town goes into defense mode where everyone in the town will try to hold them off and people in other towns will try to travel there and surprise the monsters from the back. If the monsters manage to invade the center of the town, for example, Escher, if the monsters manage to invade the center of Escher (The statue), then Escher would be filled with several tough monsters at all times until someone can manage to walk and touch the statue in the middle of the town.
Do you mean ravage? I think so, so the monsters should ravage the town... oh say... every 6 hours? To answer the last question, if the people ward off the monsters successfully, they will already get the exp and drops of the monster and I think that's enough. Anything more will make the game too easy and characters too strong too fast.
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you play too much MU