Aside from offers for purchasing rubies in the game you will also be presented with offers for various in-game items and equipment. Rather than requiring you to purchase rubies to unlock the offers you will instead be required to spend rubies already on your account. These offers couldn't be simpler as they state exactly what you will receive and the cost in rubies for the item. Simply hit the purchase button, the rubies will be removed form your account and the item/s added to your relevant storage.
These offers appear randomly on your account and so the support team are not able to trigger any specific offers, if you have a missing piece from an equipment set or there's an item you really want it is sadly not possible to directly request that the offer appear for you, nor can items be purchased on request but keep playing, building and strengthening and in-time the offers will pop up for you!