Is it possible to make a stand-alone game out of an RPG franchise's perennial first enemy? Yes.
In this RPG/action/strategy/pokemon style game, you play as Rocket, the de facto embodiment of Dragon Quest slimliness. In other words, you are a little blue slime. Yes, the same little blue slimes that we, as RPGers, have immorally destroyed to go from level 1 to 2 in so many of the franchise titles... so much so that the developers probably felt it was owed to the slime community to not only make a game out of their culture, but also make the 1 HP 1 EXP 1 GOLD bag o' blue the star. Anyways, you play as Rocket. In an incredibly quick turn of events, your entire village of slimes is kidnapped, the town destroyed, and you are left to fight against an army of beings from a very close branch of slime evolution, the "Plob". Standard RPG fare, except for one catch, the Plob drive gigantic tanks, giving this game the unique element it needs to be cool and not just fan service.
How does a 1 HP 1 EXP 1 GOLD slime fight against an army of tanks? Without spoiling the story (which, if you pay attention to, is hilarious), you get a tank of your own. The game itself then condenses down to top-down action adventuring, Legend of Zelda style, sprinkled generously with many boss fights. The adventuring is pretty standard, although you are no longer controlling a person with appendages, so you have to get used to blob mechanics. You attack by either throwing objects or slingshotting yourself at opponents, and you have quite a few nominal puzzles in terms of carrying numerous items around. You can carry up to three on your head (in totem-pole fashion), the order of which sometimes makes a difference. A primary objective of adventuring is carrying items (and enemies, BTW) to the train tracks to be sent back to town for your collecting addiction. This is the pokemon part of the game, wherein collected items will be used for tank ammo or alchemy. Additionally, you will be rescuing the slime-napped townsfolk to help rebuild the town, as well as providing tank support (explained next).
However, the unique part of the game comes from boss battles, or more accurately, tank battles. Basically, a tank battle consists of you loading ammunition into one of two cannons. One shoots straight, the other lobs and any ammo that successfully hits the other tank usually does damage, or some special effect. A successful hit only depends on one thing, and that is if your ammo is deflected by ammo being fired at you at the same time. The strategy thus becomes trying to block the enemy salvo with your own (hopefully cheaper) ammo, and follow that up with very damaging ammo that you have been saving for the right moment. The damaging ammo usually comes in varying speeds (arrows being fast, giant mines being slow), but you also have shields which deflect multiple salvos, mirrors which turn back the enemy salvo (very useful), etc. Obtaining ammo is also part of the strategy, since you have several different ammo dispensers located on two different floors of your tank. This sounds and is inefficient for actual loading of cannons, but in a game, provides an interesting complication (especially since different tanks have different layouts). The ammo is dispensed randomly, so even though you allocated a handful of big bombs in your arsenal does not mean you will actually get them right away. However, your ammo never actually runs out, so you don't really need to conserve your shots.
Another interesting twist to the battle is the ability to infiltrate the other tank. You can do this either by firing yourself over (and risk getting shot down), or by knocking on the front door (which requires some hard knocking, i.e. blasting through). You do the latter by literally running outside of your tank to the enemy tank. Why would you want to do this? Well, it turns out, the inside of the enemy tank is extremely vulnerable. You can destroy computers on the wall to slow down ammo dispensing. You can generally mess with the enemy (as you would during the action/adventuring parts) to prevent them from loading ammo. You can steal ammo and take it back to your tank. And all of this can be done to you as well. As you can see, tank battles are not that straight-forward, but it does make them extremely fun, and all of these different strategies combine for a variety of ways to attack the enemy (and can be done online!).
Your support slimes are basically automated characters that act in a specific way. Such as loading ammo quickly, or firing themselves out of the cannon, or infiltrating the enemy tank, or stealing ammo, or protecting your tank against infiltration. They come in very handy, especially while you are doing the infiltrating.
All-in-all, the tank battles make the game better than your average adventure game. The cutesy graphics and story, combined with reasonable adventure controls (you only use 2 buttons, surprisingly), make the game fun, but would be forgettable if not for the tank battles. Past the main story, there are enough collectibles to make the game about twice as long, and the multiplayer does just enough to ensure a more difficult game experience (the computer doesn't get too difficult, not even the last boss). I give this game two slimes up, and out the cannon.