How to Train Your Dragon, released earlier this year, is a good animated film about a Viking boy and how he comes to be not quite a wimp. Also there are dragons. It's a great film, you should see it!
The game based on the movie, however, is not as stellar a piece of media.
The game actually takes place a little time after the movie ends, when the Vikings and dragons have made amends. Now dragon riding is a regular thing, culminating in combat tournaments to see who the best dragon rider is amongst the Vikings.
The game is, for all intents and purposes, a fighting game. There are six dragons to choose from in total - the five that appear in the movies (the Nightmare, Night Fury, Zippleback, Gronckle, and Nadder), and a secret type that is unlocked by completing the story mode. Each of the dragons have the same combos and the same abilities, though they differ in minor ways, such as the speed of their attacks, or how far their attacks reach.
All in all, just the simple dragon selection is fairly disappointing. In the movie, as the main character picks up a compendium of dragons, we get a glimpse at a dozen dragons that don't actually make it into the movie. These would've been perfect in the game. Unfortunately, we just get one extra dragon, which of course, has the same moveset and abilities as every other dragon.
Combat is simple: every dragon has a strong attack and a weak attack, and combos composed of these two moves. Each dragon also has the ability to breathe fire, and can charge up to two levels of fire-breathing destruction, which takes time but tends to pay off. Though there are a number of options available to you for combat (though not a lot), fights typically boil down to pressing buttons really quickly, and your success pretty much depends entirely on whether or not the computer opponent attempts to interrupt you combo mid-strike, which can be pretty irritating.
It's not a really deep combat system, and even considering the target age of the game, it's a disappointment. Fights are typically either extremely easy (see my strategy above), or extremely frustrating as the computer blocks everything you throw at it before interrupting you, with nothing you can do about it. Fights are dull, either way.
The story mode is the real meat of the game. In it, you take either Astrid or Hiccup (no change to the story, except for what dragon you start with), and lead them to the Viking Championship. To do this you must fight your way through a series of tournaments, completing little quests in between them, as well as training, taking care of, and strengthening your dragons.
Though you start with one dragon (a Night Fury if you're Hiccup, and a Nadder if you're Astrid), you gain more as you complete tournaments. And these dragons need to be trained to earn experience points, to level up and make them stronger. Experience can be gained in two ways: either completing training, or earning medals in challenges. While this happens you need to take care of your dragon's needs by feeding them various ingredients, lest their health in battle be decreased.
Training is what it says on the box. For each level of training, you are given a new combo or ability, and must use it to defeat an opponent, netting you some experience points. The challenges are a little more involving, requiring you to fly through hoops, deliver sheep, memorize patterns, and so forth. They're a little fun diversion from the combat, and also earn you some money and ingredients to feed your dragon, but little else. Earning experience from these abilities gives your dragon characteristic points that you can use to increase its various abilities, making it tougher. It's not very in-depth, but does the job of making you feel like your dragon is growing in strength. You can also customize your dragon visually in a number of ways by using parts that you unlock via leveling up.
There are a good number of issues with this game, not the least of which are related to the repetitive combat. Characters spit out one-liners constantly, whether smashing barrels while running around town or fighting opponents. The camera control during these periods is also spastic, jumping around, not quite sure where to go. And for some reason, the game has a tendency to slow down considerably from time to time, which really shouldn't be happening on a game like this. And loading screens, though not long, pop up often enough that they become a bit of a nuisance.
If it's just fights you're looking for, the Arcade mode will allow one- or two-player battles. You can either import dragons that you've cultivated in the story mode, or play using 'legendary' dragons, which are just the regular six dragons with varying attributes.
There were many ways that a game based on How to Train Your Dragon could've been made, and this is certainly not the worst of them. The idea is sound, and kind of interesting in concept. The graphics do well to highlight the dragons (though not much detail on the human characters is present), and voicework is also pretty solid.
However, the lack of variety in the dragons, both in basic design and in the movesets, make the game's central focus - the dragon combat - a bore. It really just feels like you're pressing the same buttons over and over again. The battles are typically too lopsided to be very enjoyable, anyway, and the only way computer opponents can win is by simply interrupting you in the middle of a combo, something that you have no defense against.
When it comes down to it, if you're really, really interested in seeing a bit more of the world and character from the film, then you might have some enjoyment with this game, but just a little. But without some varied combat or something that doesn't feel like filler, it's hard to say that anyone else will enjoy it.