There is a lot going on in Disgaea DS. It is a tactical role-playing game similar to Final Fantasy Tactics for the GBA, only this one is deeper (yes, it is possible). It isn't entirely user friendly and some casual gamers might be scared off at the amount of detail there is in this game. Everyone else will just love it.
Laharl is the on-screen character as he walks around his castle, which also acts as a hub to all the different places you can visit. While in the castle you can heal, buy items, create characters, talk to NPCs and do a variety of different things. Once you enter a battle you can choose which characters you want to have participate and dispatch them at your will.
The controls can be utilized with either the touch screen or the directional pad and the A, B, X, and Y buttons. In the castle, Laharl moves really fast, so I found the touch screen and stylus to be a simpler way of moving him. However, in battle the directional pad seems more precise.
Battles in general are different from any other tactical RPG I've ever played. After you dispatch your party, you have a lot of options to choose from including attack, special attacks, lifting and throwing enemies or party members, and so on. Also, you can either execute each move one at a time, or you can move all your characters into place and execute their moves all at once in the order you placed them. This degree of specialization is nice, but it can be confusing at first. It isn't initially intuitive, but once you get the hang of it you will love it. Don't worry, there is a nice tutorial to help you out. Oh, and characters that die in battle are not dead for good! You can revive them back at the castle.
There is another unique feature of Disgaea DS: The Dark Assembly. In the Dark Assembly, you can create and delete characters, or call on all the senators to vote for a proposal you have in mind. Proposals are for things like getting better weapons in the stores and so on. If not enough of them approve your vote, you can bribe them. It's about the most realistic political simulator available today. Also, in order to do anything in the Dark Assembly you must have mana, which can be collected by killing enemies.