An stands for “Nintendo Submission Package.” This is the format used for digital eShop downloads. NSPs are generally smaller because they strip out unused cart filler data, but they require installation to the Switch’s internal memory or SD card.
Assuming you have a modded Switch (Atmosphère CFW) and a legal dump: tactics ogre reborn switch nsp xci update extra quality
Here are some general tactics and strategies to help you succeed in Tactics Ogre: Reborn: An stands for “Nintendo Submission Package