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Although the lockboxes containing the items are indestructible, the items themselves are not. So be careful with exterior explosions (AOEs penetrate models), and avoid shooting the expelled item after the final lock is opened (See Toastie link above)! The Skunk can equip two shields simultaneously and the completion of either mission allows the purchase of two. The duplicate mission can be considered a chance to reconsider an earlier choice or a second chance in case of misfortune.
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