A solid and gritty old-school shooter
As a big fan of the Contra series, I was skeptical when it went into the hands of WayForward. This was mainly because of all of the games that they had previously developed (http://www.giantbomb.com/wayforward-technologies/65-2294/), which was kind of unsettling. However, Konami picked the right developer for this game. It's packed with features and (despite the game being only six levels) it will take you weeks to beat this incredibly difficult game.
I am a huge fan of 2D sprite graphics. I like all of the new realistic graphics, sure, but 2D sprites hold a place in my heart. The talent behind the sprites in Contra 4 is absolutely stunning. Massive bosses span both screens of the DS and beautiful backgrounds cover each level. While keeping true to the original Contra games (most specifically Contra III), Contra 4 goes over and above what is expected of 2D sprites.
The sound, while staying true to the original, is very good. It blares out of the DS speakers louder than any other game I've put in my DS before, however, so I found that I bit startling. The music is remixes and original tunes inspired from the original, while the sound effects sound pretty realistic. While WayForward could have done more with the sound, what they did was sufficient.
Many people argue that graphics are the most important aspect of a game, but I disagree. Everything must work together in an intricate way not unlike a clock. However, like clocks, some parts are more important than others. That aspect is gameplay; crucial to the game. My God, does WayForward nail it. The action is fast-paced, gritty, and exciting. You'll always be holding down the Fire button in fear that some enemy will fly down or jump up and kill you. If you thought other Contra games were difficult, this one will change your mind. There will rarely be a dull moment for you, even if you're playing on the unsuitably-named "Easy."
The level-design is unique and interesting; adding to the gameplay in exciting ways. For example, one level makes you climb up a missile that is firing up into the atmosphere (whilst dodging smaller missiles being fired at you and warding off enemies), and then attempt to survive as it makes its descent towards earth. Many of the levels force you to think, "What can I do next?" but only gives you a split second to solve it.
The controls in this game are superbly done. They respond quickly, and are simple enough to remember. I only had one problem with the controls. The X and Y buttons were so close together that I accidentally hit one when I meant to hit the other. Despite this, the controls were well-down; while they also stayed true to the original.
The bonus features in the game are nice little distractions that you can look at while you attempt to ward of the frustration of dying again. The gallery contains information, screenshots, and box art of all of the Contra games of the past. For older gamers, this is a trip down memory lane. Younger gamers can learn about the old-school days of Contra. I constantly go and look at it, since it is a nice little feature.
Also packed into the tiny cartridges are Challenges. I know you're thinking, "As if the actual game isn't enough of a challenge," but this feature is fun. While you don't unlock it until you beat "Easy," once you do you will go back and play it over and over.
In conclusion, this game is incredibly difficult. I'm sure that if you're interested in Contra, you already know this. If you didn't, now you know. Anyways, this game is so difficult that sometimes you may feel like throwing your DS against the nearest wall. As a matter of fact, I recommend using an Action Replay DS to gain infinite lives so you don't have to break your DS in anger.
Overall, however, this game is a great game. For any gamer looking for a challenge, I recommend picking it up. However, beware, this game is not for the faint of heart.