Remember the Final Fantasy Tactics games on the gba and ds or Tactics Ogre or Shining Force? Well this is a fantastic homage to the gba era strategy games. Not Final Fantasy Tactics level but far better then the others on the gba.
Story does it matter? Nope. The level design is perfection for the handheld. Just one screen maps that you can finish in twenty minutes at most. The downside is you need to open up the chests and do your searches while playing the chapter, if you replay a chapter you get experience points but chests and treasures are gone.
Even better when you fnish the game they give you extra levels called Ex Stages in the Free Play mode but you have to be level 20.
Hint max out throw stones its amazingly effective for your soldiers for the first turn. Also always have a character do an action even if its healing yourself when you do not need to. Every action outside of attacking gives 10 experience points and each level is 100 points.
So on your 3ds go to the eshop and search for Mercenaries 2. Mercenaries 1 does not seem to exist unless its Japan only. Best five dollars spent on a game. A first playthrough took me 19 hours.