My god... Wyvern got at least 5 times of Ghoul's health! How can you defeat that with only 4 puny humans? It also can one hit kill like Ghoul and have higher chance of miss attack than Ghoul (at least I think so). Surely if someone do defeat that monster he gonna get something worth the effort right?
Edit: Is the ending can only be activated right at that week when you get the age up notif or you can activate the ending sequence any time after you got 1 year? I mean even if you do set the timer wrong. I skipped the week by resting and went to the beach (i assume by beach you mean the place where Billy always hanging around, considering that's where Billy goes when he left a note saying he went to the beach) but nothing's there. I tried to skip the week again but still nothing on the beach.