The Open Architecture (オープン・アーキテクチャ?, lit.: "Open Architecture") is a treasure in the European and Japanese versions of Pikmin 2; it is actually an open can of Maruha Nichiro Akebono salmon. It is found in the Citadel of Spiders, on sublevel 3. Yellow Pikmin are rather useful here, among the Anode Beetles and Swooping Snitchbugs. This particular treasure is most often found out in the open in one of the main rooms, easy to locate and collect once the enemies have been dealt with.
In Pikmin 3, there is an item similar to the Open Architecture, but it is only for decoration and has no purpose in the game. This is where the tutorial with the Yellow Pikmin takes place.
“I discovered a metallic container. Unfortunately, it was already empty, so it is going to be tough to sell. Some sales talk will be needed for this. Let's see what the ship says about it.”
Sales pitch
“The ultimate in reverse psychology! If it's too open, nobody wants to steal it. Its[sic] a shame though, that the contents are so clearly visible.”