You'll use the DS touch screen constantly as you put together various pieces to make walls, towers, and weapons. Initially, you'll deal with a touching, dramatic story as you get a half-hour-long, interactive tutorial on how to build and protect your town. This tower defense-type of game goes beyond strategy to include role playing elements. Not only do you build strong structures, as you kill off attacking soldiers, you level up (get more powerful) as well. And as you get rid of Clockworks, you get money called Source, which you employ to build more structures. There's a lot here!

Lock's Quest may be rated 'E', but it's for an older kid. That's because the items, sometimes millimeters in length, may be too tiny for kids to pick up and use, even with the DS stylus. Plus, the difficulty level of the strategy you must use ramps up appreciably in the later levels. Still, there's so much game here -- over 100 quests. And some can be played with one another person using the DS' local wireless multiplayer ability.

If you like tower defense games on the DS, this is the first. You can keep an eye out for another anticipated tower defense game which is coming in fall 2008 called Ninjatown.