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Items sell for 3/4 of their original value. You can carry a maximum of 16 - any picked up after that will require that you discard one.

[edit] The secrect shop

In addition to the normal shops that appear at the beginning of every level, there is also a 'secret shop' that allows you to buy many rare and useful items.

To access the secret shop, you have to be on the screen that shows up at the start of every scenario--the one where you hire troops, equip items, etc. Press . You should hear a special sound to indicate your success. Now, go to the shop menu. The shop for the current scenario will have been replaced with a new one.

[edit] Items available