You can combine these together:
Harpoon Gun: the function of the arrow(bullet) sticking to target
viewtopic.php?f=61&t=15010VED Grenade Launcher: “The longer you hold fire, the further it goes”. You may also want the Trajectory Guide and custom ammo(arrow) function.
viewtopic.php?f=61&t=17551I'm already making a project, so it's a pity that I can't offer help this time. I suggest you to learn some simple part of lua, it'll be helpful when you want to make something: just download other mods and learn their code, at last you should be able to create new ones.
And, sprites shouldn't be the problem, right?