in my opinion a boomarang would be a really cool item, and to get it, you would need to dig it up from a grave. It would break pretty easily and it would not do that much damage (probably the same amount as a shovel). If you get some flint and a couple of webs, you can add some sharpness to the boomarang (when upgraded, it would do the same amount of damage as the spear, but the durability would run out much faster than before)