Guild Wars 2

My suggestion is to add an item (prbbly to gem store) that will alert you whenever one of the elder dragons(Tequatl /Shatterer/ Jormag) is available in the server – people would gladly pay 600 gems for this item.
you can also have Crystal Orbs for other mega bosses for 200 gems.
gauranteed to be your best seller

attached a mockup photo – notice both text in the middle and orb on right
Thanks

you could just look at the various websites with timers, its not 100% accurate but gives a good idea as to the timing, scratching that, some guild members would announce when they arrive
(edit) not to mention that very VERY soon, tequatl will be revamped and most likely have an announcement in the living story area of the UI

I’m aware of these sites (and mobile app )- I’m suggesting a better and more authentic solution.
Just like you have GW2LFG.com for parties and in the Taquatl patch they are going to add the same functionality to the game.