Instructions
Golden Hammer Weapon
Start a brawl match.
Select the "Rules" button on the character select screen.
Turn every item in the game off, except for the Golden Hammer.
Start the brawl match. Every item that appears on the stage will be a Golden Hammer because it is the only item allowed to spawn.
Golden Hammer Trophy
Unlock every character in the game. This is optional but significantly reduces the average score you will need for each character to unlock the trophy.
Compete in the Home-Run Contest with multiple characters.
Earn a combined total of 45,000 yards in distance between all your characters. Repeat the Home-Run Contest for characters with distances less than 1,000 yards if you complete the Home-Run Contest for every character without reaching the 45,000-yard mark. The Golden Hammer trophy will be unlocked as soon as you hit this mark.