The obsidian platelegs are part of untradeable and degradable obsidian armour set. They require level 60 Defence to wear, and can be made by smithing three obsidian bars, requiring level 80 Smithing. Obsidian bars are made by smelting obsidian shards, which are dropped by monsters in the Fight Cauldron.
In addition to its defensive bonuses, they provide a 12% reduction to damage from creatures and players in TzHaar City.
With an update on the 30th April 2013, the armour no longer triples damage taken by you when fighting in PvP or any other monster.
When used with the rest of the obsidian armour and either an melee, ranged or magic helmet, it will increase your accuracy by 10%, very similar to the Void Knight equipment.
The obsidian platelegs degrade after 4,000 hits. Once they fully degrade they cannot be reused, and new platelegs must be smithed. However, they can be repaired before full degradation with obsidian shards by using the shards while wearing the armour to be repaired, at a rate of 100 charges per shard.
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