Whats the best longsord or hammer to use against the shen gaoran. And do..

Against the Shen Gaoren, timing is important. You have to time your attacks just right so that they don't miss his legs, and so that you can interrupt it when it's about to attack the town.

Shen is weak to Fire and Dragon, so use the Dragonbreaker. For Dragon Longswords, you can use the Fire Dragonsword, made from Lao-Shan's materials. Fire hammers are the Gunhammer series, and for Fire longswords try the Wyvern Blade 'Fall' series.

Attack his legs starting with the earliest one you can get to. When the leg turns red, attack another one. If Shen Goaren falls, quickly go to his face and attack there. Or bring bombs and put them there, then blow them up. Use the Dragonator when he's about to fire his acid. Keep attacking his legs until they all turn red, then keep attacking. After some more damage they will turn to gray again. At this time the Gaoren will fall and stay down for longer. Attack his face, then attack his legs again when he gets up. They'll turn red again and soon he'll die.

Stuff a hammer or sword use a heavy bowgun an lots of pierce and graigs and clusts. Bring extramaterials to make extra bullets