Trident like weapon

First half: Easy. If you don't know, in the create mod element tab, there is one called Ranged item. Click on it. When you select item for ammo, you'll notice that you can't select what you're trying to make, because it doesn't exist. To make the item deal damage when used in melee, make sure to tick the check box next to melee damage. Put anything in the ammo require slot, and same for item representing texture of bullet. Once you click save mod element, go back through it and you will be able to change the bullet texture and ammo item to itself. As for returnable, I don't think that's possible, and if it is, then you will almost definitely need to code raw Java to make it.

Thanks this is really helpful!