Is there a rotation about Black Lion Chest skins?

[Syanur.2635]

So I would like the Hydra Staff. It is only available in Black Lion Chests. So I was wondering if there was a rotation about old skins availability in BLC or if it was random to Anet’s will. Is there anything written somewhere telling me when I would be able to acquire it?

[Inculpatus cedo.9234]

There's no pattern that I know of. A particular item may return to the Black Lion Chest, or may move to the Black Lion Statuette vendor.

https://wiki.guildwars2.com/wiki/Hydra_Staff

It's available now in the Black Lion Exclusives Chest. https://wiki.guildwars2.com/wiki/Black_Lion_Exclusives_Chest

The BL Exclusives Chest can occasionally be found in Black Lion Chests, as well.

 

Good luck.