Maybe I'm way behind the times in Castle Age here - I just figured out something rather game-changing about the Bronze Ingot Stack of Piercing (BISP) in the conquest duel shop. BISP grants +25 physical piercing, each 10 points of piercing is effectively +1% attack in PvP, so if your raw attack stat is, say, 1000, then forging a BISP on your weapon gives +25 attack.

For comparison's sake, you would have to level an attack rune to L6 (at 5 att per rune level over 1) for the same +25 bonus; but the BISP bonus will grow with raw attack, while the attack rune bonus is static with rune level.

At first I assumed this forced a choice between attack rune and BISP on one-slot forge-able weapons (e.g. Living Death). The choice is obvious with my raw attack stat of 3000: attack runes would be obsolete. But no, it turns out the rune slot is a bonus on forge-able items. On a 1-slot item, you can forge 1 rune AND 1 gem or ingot. As soon as I figured this out, I slapped a BISP and attack rune on my Living Death sword.

This also obsoletes the +10 pierce Warbringer Gauntlets, and stops me having to swap between piercing and damage-rune in the glove slot. Just forge a BISP and damage rune on Knight's Bone Gauntlets or Vanguards Gauntlets. Pow.

There's are currently only 2 items in the game with 2 forge slots: Commander's Bone Plate, and Duke's Bone Blade. As far as I can tell, Bronze Ingot Stack of Resistance (BISR) cannot be purchased - it must be created from alchemy, by farming 16 ores from monster drops. So top-shelf defense is currently quite a bit more involved than offense.

2-slot items cannot take 2 ingot stacks - they must be diversified with an ingot and a gem. At this time, there are 2 tiers of elemental gems: "dull", +15 elemental offense ("fury") or resistance ("protection"), and "shining" (25 offense/resistance). Currently the second tier is earth only: "Shining Gem of Earth Fury" and "Shining Gem of Earth Protection".

So, when I someday unlock Duke's Bone Blade rank with its 2 forge slots, I can load it up with attack rune, BISP, and an elemental piercing gem if I care to. This renders the Warbringer Longblade (+20 piercing, 1 slot) a showpiece item at best, because even with its base 20 piercing plus a BISP for total +45 pierce, it can be topped by a Duke's Bone Blade with a BISP (+25) and Shining Gem of Earth Fury (+25). Hopefully by that time, there will be a wider variety of second-tier gems available.

(Revised to reflect the correct bonus % bonus, originally though 1 pierce or resist = 1% att or def)