Guild Wars 2

In the PvP rewards section , there are sometimes four tiers of weapons whereas there are only three crafting tiers – Arcane Orbs, Arcane Crystals and Arcane Slivers.

This means that two items share exactly the same mystic forge recipe. Here is an example of one such pair: http://wiki.guildwars2.com/wiki/PvP_Forest_weapon and http://wiki.guildwars2.com/wiki/PvP_Valley_weapon .

So how does this work? Is it random? Is there something else I’m missing?

random as everything which is related to mystic forge

I think that you have to “crit” to get certain weapons and gear using certain recipes — at least that’s the term that I’ve heard used.

bhagwad.4281:

In the PvP rewards section , there are sometimes four tiers of weapons whereas there are only three crafting tiers – Arcane Orbs, Arcane Crystals and Arcane Slivers.

This means that two items share exactly the same mystic forge recipe. Here is an example of one such pair: http://wiki.guildwars2.com/wiki/PvP_Forest_weapon and http://wiki.guildwars2.com/wiki/PvP_Valley_weapon .

So how does this work? Is it random? Is there something else I’m missing?

I think that in certain Tiers, where this happens.. one of the items will only be generated upon a “crit” when being crafted by the Forge.

I’m no expert on it however and it seems that very little research has gone into the recipe specifics on the PvP side of things. Once a general formula pattern was discovered, not much else was researched.

In that case Valley is the regular weapon and Forest is the crit. Usually the crit for Orbs is the same you get as regular with Crystals and the crit with Crystals is the regular with Slivers.
You can check this guide for more informations:

http://www.guildwars2guru.com/topic/55030-pvp-mystic-forge-recipes/