While we're on the subject of DS classics, here's an even more obscure one: Over the Hedge.

While admittedly it never quite got the time in the oven it deserved, being a release tie-in with the movie and put out alongside all the console versions, this one in particular was something special. It's a third-person over the shoulder perspective stealth game with tank controls, sneaking into the hilariously well-protected homes of humans to steal their junk food. And if that wasn't enough, it had you managing two characters in real-time by swapping back and forth between them, using their varying strengths to defeat the ridiculous laser alarm systems and traps along the way. It's slow paced and relatively simple, and I used to have a blast finding ways to completely break the game because the devs didn't have enough time to iron out all the kinks entirely, but it never quite got the attention it deserves for being such a unique labor of love.

I have to give it massive props for having so much creative heart when a tie-in for a mediocre animated movie has no right to be that good. The developers saw the opportunity to make something that put its source material to good work instead of just another hack-and-slash romp (like the console tie-ins were) or a minigame collection (like the later DS game (???) was) and their dedication to the craft of game development really shines through some of the jank involved in its presentation and sometimes wonky physics. By now, a unique take on a stealth game is nothing all that special, but at the time this was one that really grabbed me.