Easier difficulty aside, this is still a fantastic Ratchet & Clank game that ranks upon the best of the series.
Ratchet & Clank hasn't changed much from it's predecessors. After the darker, and more shooter based game, Deadlocked, Tools of Destruction returns to its light-hearted, platforming based gameplay (even though Deadlocked was still fun as hell!). If you've been playing Ratchet games, you know what to expect... fast paced, non-stop action, creative puzzles, and tons of unique and fun to use weapons. Tools of Destruction is no exception.
Anyway, the game introduces its latest villain, Tachyon. Tachyon knows many secrets about Ratchet, and the Lombax species. Ratchet decides that he wants to know more, so he attempts to find Tachyon and get some answers. Meanwhile, Clank meets some new friends known as the Zonis'. They tell Clank things... important things. They go on a giant adventure and a lot of things happen and a lot of things are introduced (such as the dimensionator). All of those interesting secrets will be revealed when you play the game. Basically, it's a fun story like all other Ratchet & Clank games, except it answers more questions, making it EVEN BETTER!
The gameplay is pretty much the same, but some things have been added. One of the major things added are Devices. Devices are low quantity (usually about 1-4 at a time) weapons that are a bit more expensive. Examples include the Groovitron, Leech Bomb, Helivisor, etc. These can only be purchased at a specific store (the gadget store!). The absence of different armor from Deadlocked, has been fixed. There's now a special armor store like previous games. Each piece of armor you buy absorbs different amounts of damage, with the most expensive absorbing 65% of damage (That'll cost you 10,000,000 bolts, by the way).
Weapons are... like most Ratchet & Clank games, inventive and fun to use. You have your basics like the Combuster (machine gun) and the Fusion Grenade (bombs) as well as the obviously unique ones, such as the Tornado Launcher (guess what it does!) and the MAG-NET Launcher (it captures your foes and gives them the electric shock treatment). As opposed to the disappointing 10 weapons in Deadlocked, TOD features well... a lot, and they're all fun to use and inventive.
The game features some puzzles/mini games, which aren't terrible, but not necessarily needed. You get ship battles... but not the more advanced ones found in Going Commando, these ship battles are basic go straight/shoot stuff/go through rings/shoot more stuff. They're similar to the ship battles featured in Size Matters.
The upgrading system is previous to past games. The more you use the weapon, the more it upgrades. There are 5 levels, yeah awesome. BUT WAIT! There's a new little feature. With the new currency in the game... Raritanium (not exactly new; it's been featured in past games, but mainly for ship upgrades/trading for bolts). The Raritanium is used to upgrade your weapons in a variety of different ways, such as giving it a higher ammo capacity, increasing its power, increasing its rate of fire, etc. If you've upgraded the right things you can even added a little special to the weapon. Raritanium can also be used to by the Golden Groovitron, but that's another story.
Speaking of golden weapons, they're back! After beating the game, you can go through challenge mode, which bumps up the difficulty, but lets you keep your old weapons, and gives the power to upgrade them even more by turning them GOLD! Challenge Mode, like past games, is fun to play, and certainly kept me replaying the game constantly, trying to upgrade my weapons, search for skill points, etc.
Overall, TOD is just as good as previous installments, if not better. I'm not sure if I can really call it the best in the series, but it's a fantastic game, and if you love the series like I do, you shouldn't pass it up.