Eventually, Rocket gains a flute that allows him to summon a Godzilla-sized tank he, (and later AI-controlled crew members,) actually move around inside, collecting ammo from dispensers and throwing it into either of the tanks two cannons. (One shoots straight, the other in an upward arc.) This is where the real joy of the game comes in. There's so much to do in tank battles, they could be a game in themselves. (Actually, once you've beaten the main game, it pretty much is the game- in multiplayer.) Different types of ammo have different properties such as speed, damage, and amount of opposing ammo they can come into contact with before being taken out. Which ammo to arm your tank with, as well as what to launch from which cannon, in what order, and when make up half of the strategy.

Aside from loading cannons, you can give orders to your 3 crew members, hand-picked by you from amongst townspeople you've rescued or monsters you've collected at least 40 of. (My favorite is the Goodie Bag, which is by far the most difficult to get, as they rarely appear and are hard to catch when they do appear.) You can also break into the enemy tank (there are a few ways to do this,) and start wrecking their computers so as to make things not work as well for them and/or steal ammo to take back to your tank and launch at them. Between you, your opponent, your crew members, and theirs, there's a lot of fighting going on beyond just what's being shot out of cannons. (Best way to get an annoying enemy out of your tank- toss them in your cannon and launch it back at their own tank- possibly blocking one of their own incoming shots in the process.)

You also eventually gain the ability to do alchemy, which lets you combine various items and ammo to produce more powerful ammo. This is what there is to do even after you've rescued everyone and gotten all crew members. Depending on what ammo you want, this could take a very long time. My only complaint about the game is that the story mode is far too easy. It's a ton of fun in any case, but I never felt in danger of running out of hit points, especially once I had collected a few of the games numerous extra hearts, (just like in Zelda.) There were a few tank battles that provided a good challenge, but it's much more fun to play against a human once you've gotten your tank all decked out and have more advanced ammo. (Did I mention you can also collect materials and money for tank upgrades?)