information; weapons

Rikku's offensive weapon is the claw. Well, it's called a claw, but can be described more as "very-sharp-knuckles" or possibly gauntlets.
Here's a full list of them taken from the official FF10 stragedy guide.

As for Rikku's defensive weapon, it's a targe. Now, according to my oh-so-new English-Finnish dictionary targe means shield (to all you non-English national speakers). Makes sense, since it's supposed to protect her, ne? Here's a list, also taken from the stragedy guide.

I typed all this with my own hands from Piggypack's Stragedy Guide, and man was it tiring! So, if you use all the info and stuff (which I kinda doubt, it's an awful lot of weapons...), at least don't claim to have written it all yourself.

getting godhand

Name: Godhand
Abilities: Break Damage Limit, Triple Overdrive, Douple AP, Gillionare

Aboard Airship, you must enter the password GODHAND to access a new destination at the Mushroom Rock. After walking quite a long way to the north, you come across a chest containing the weapon.

You'll get the Mercury Crest at Sanubia Desert- West (north-west from the entrance to the valley)

To acquire the Mercury Sigil you must complete the mini-game THE VALLEY OF THE CACTUARS

THE VALLEY OF THE CACTUARS

Valley of the Cactuars is a minigame you have to complete in order to acquire the Mercury Sigil. It takes place at Bikanel Island. The sigil is in the actual valley, where you can't go because of the sandstorm. So the purpose of this in-the-end-nice-and-easy minigame is to tame the storm.

There's a cactuar stone south of the valley. Examine it and you receive a hint where the first gatekeeper can be found (complete list of locations and whatsoever here [pop-up])

After finding the cactuar, you have to play a little game with it. Run towards it, if it has it's back turned to you. As soon as it turns to look your way (needletime!), stop moving. If it catches you moving, you lose and receive a Sphere del Perderor. You have three chances with each cactuar. If you win, you'll have to fight the cactuar, and after the fight you get a sphere named after the cactuar.

Go and insert the sphere to the cactuar stone, and you receive a hint of the next cactuar's hiding place.

In the end, after all ten gatekeepers, a very sad poem (pop-up) will be read to you (...come on! The cactuars died! You killed them even though they did nothing to hurt you!) and the sandstorm dies out.
In the valley are two chests. One of them contains the Mercuy Sigil and one has a different item depending on how many gatekeepers you catched.