Legendary Items and Mystic Forge

Legendary weapons are hardest to make in this game, But they look amazing and you will have to invest time to make them. They have special effects and nice visual.

http://gw2legendary.com/ This website Shows all items you need to Forge them.

Here visual view at them:

Hardest part is to get precursor due its drop rate is verry low or you can try to forge them in mystic Forge: 

Mystic forge will be required when you will want to craft Legendary due you will have to forge all parts in to a single weapon.

In Mystic Forge you Have a lot of different possibility to forge things.

Here is list of items you can craft there :

https://wiki.guildwars2.com/wiki/Mystic_Forge/Equipment