Can't use spear gun.

[SarahGirl]

Is there a secret to using the spear gun on the crabs on the viridian coast. I grab the spear gun, but it won't fire when I click lmb or use the #1 key. When I switch back to sword, its all good, I can fight like normal but it doesn't count toward the quest when I kill a crab with my sword.

[fatalystic]

It seems to stop working when you shoot the big crab, which is odd since it didn't happen at the beginning...

 

Killing stuff without the gun's supposed to count.