This item drops off one of the Animated Weapon monsters in Dynamis-Xarcabard. Once you defeat the 15 Demon NMs needed to spawn the Dynamis Lord, these weapons will also spawn. They are all over the map, so finding the right one can be tricky.
Animated weapons look like all other arcana weapon monsters, with a slight exception: There's no critter underneath the floating weapon. It is just a weapon, floating in the air.
The weapon you are looking for is, obviously, a hammer. These creatures hit HARD, but there isn't much of a problem with fighting them. An important thing to remember, you MUST be using 4th stage Gullitani against this monster. It will flee, and despawn, if you don't use Randgrith on the monster every minute or two. So, to win this fight, and get your Heavenly fragment, you have to "Keep the monster interested." Use Randgrith, and it will continue to fight.
You will need your club skill to be capped, and wear a LOT of accuracy gear. Sniper rings (or something similar), Reverend Mail, if you're /NIN then equip a Pixie Mace in the offhand weapon slot for the Accuracy+5 from that weapon, or a Martial Wand for the TP Bonus effect, Life Belt, Optical Hat, etc. Sole Sushi is good food for the fight, and having a COR use two hour ability has an 80% chance to give you at least enough TP% for a weapon skill. Bring an Icarus wing, and use it if you miss the monster 3 or 4 times. Be sure to fight monsters beforehand, or use an opo necklace and sleep potions so you can start off with 100% TP.
Have someone ELSE haste you, so you spend all your time swinging at the Weapon. It is ideal to have 2 BRDs in the group with you, so you gain two accuracy songs, and two speed songs. This, along with good accuracy equipment, haste gear (blessed legs, mitts, pumps, walahra turban), haste spell, and a bit of luck, you'll have a quick, easy, successful fight, and your Heavenly Fragment.
Edited, Sep 12th 2006 at 2:59pm EDT by Soarin