Cobalt Armor

Cobalt armor is an armor set which requires 45 Cobalt Bars, or 135 pieces of cobalt ore, to be crafted, and is blue in color. Like all Hardmode-material armors, the Cobalt armor has three different headgear/helmet options, allowing players to focus on magical, melee or ranged combat, and each option changes the set bonus.

A full set of Cobalt Armor creates an after-image/motion blur effect similar to the Ninja clothes, Shadow armor and Necro armor.

Old version
Cobalt armor was replaced by Jungle armor in 1.0.3 as a name and graphic swap (everything else is equivalent). Pieces of the Cobalt armor could not be crafted and instead were dropped randomly by Hornets in the Underground Jungle. Existing pieces of Cobalt armor that players owned were converted to Jungle armor when the patch was applied, as to make more sense for it to be found in that environment.

Trivia

 * The hat, helmet, and mask appear very similar to a straw hat, a samurai helmet, and a ninja mask, all of which are common in media portrayals of Feudal Japan.
 * The full set of armor with the helmet also bears a slight resemblance to Mega-Man