@Human Lævateinn or damaged twig is Loki's weapon not surtr's. It is debated its form as it can be seen as a sword, a dart or a wand and is often depicted as a fire weapon but not always. (Also the dart part may be mistaken because Loki also made mistleteinn a mistletoe dart used to kill baldr as mistletoe was his only weakness cause when FRIGG (not freya though they are sometimes thr same character so whatever) asked everything in the realms to not harm him she thought mistletoe was already harmless and didn't bother)