What's the reason that the newly introduced Talismans are purchasable for a limited time only?

They sound be pretty essential - and I am not sure that's a good thing, although I am confident the variaty in PvP will increase in the short term. Do you plan on making them available by other means after that? Wouldn't be encouraging for players starting in the future to find out they are late to the party. Speaking of that, I still want a Guard set

Bleed still does no damage