War hammers are rather rare in most larp games, their specific job of armour breakers often not taken into account. But first to clarify something.
This is a war hammer.
This...is a cartoonish joke of a weapon.
Unfortunately the popularity of Wacraft 3 and World of Warcraft also means a lot of people get the wrong ideas and start using ridiculous designs and wearing latex house-sized pauldrons.
Admittedly back in the day when Chris Metzen was doing the Warcraft artworks they were honest to god high fantasy, not high stupidity.
But I digress, back on topic.
So - war hammer. First things first -
BUDGET - about 15$ if you start from scratch. Less if you already have some of the supplies and materials.
One polypropylene pipe, around half a meter long (F20 or F25), pipe insulation foam, duct tapes, quick glue, blind rivets, 1 meter of wallpaper with wood texture(They only sell those by the meter anyway). Plastic bottles and cardboard.
Tools: The usual for making a larp sword AND a tool for blind rivets + drill or hammer&nails.
After that we roughly shape the hammer head and leave it like that. Here is where you decided just how you want it to be, so make your pick. I decided to leave the spike and hammer head longer for safety issues. Not the best decision in regards of aesthetics but its a bit inevitable, larp boffer weapons are by default thicker than real world or latex counter parts.
Next thing to do is rather important. After stuffing the hammer head with some cardboard for thickness. Fit it to the shaft, drill 4 holes and use blind rivets to secure it firmly in its place.
Now the head can withstand allmost anything without tearing from the shaft. Don't try anything stupid to test it though.
Next we have to make sure the top part of the shaft is safe, it will be bad if your swing falls short and you break someone's nose with the naked pipe right?
With this, our war hammer is finished and ready for use. Now go find something to smash.
Here it is compared to a knife and a sword to get an idea of the size. Shorter weapons are sometimes a better idea.