save the world

you go through and as you enter you see a weapon laying on the ground. From the looks of it is a spear. You pick the spear up and look at your new options around the room. In the corner you see a level to open a passageway. As you pull the level you are greeted with the gross smell of dead fish. You walk in and inside is a big pile of bones and dead carcasses. A big monster comes forward bearing its large sharp teeth at you. Do you fight or flee and find an exit.