First off, the long time collectables of the series, stars and coins, are out. Mini Stars and Mini Ztars are in, effectively combining both collectables into one. Rather than saving up coins to purchase power stars, you continuously rack up a total of Mini Stars throughout the game. Collecting Mini Ztars will, logically enough, remove Mini Stars from your total. The person with the most Mini Stars at the end of the game wins.
The board game component of the series has also been giving a significant update. Players now all move together on a linear path, rather than exploring a board one at a time. Each turn sees a different player become the "captain" allowing them to roll the dice and continue along the path as well as sometimes receiving special bonuses for being the player in charge. The spaces on the board have all kinds of effects, from shuffling the turn order, activating a mini game, and even triggering boss battles, all while working toward the end goal. As minigames no longer follow every four turns and are instead encountered more sporadically, the pacing of Mario Party 9 is much faster than other games in the series. Gone are the days of circling the board for hours playing out turns and playing minigames over and over. Here you are making a beeline for the finish with only the occasional minigame sprinkled in to keep things interesting. It's a great new formula that really keeps things moving.
Also gone are the days of having to put up with annoying computer controlled opponents. Mario Party 9 no longer forces you to use four characters when playing with two or three players. The game plays out the same way with any number. You still have the option to include CPU opponents if you want, though.
The minigames are one part of the game that remain essentially untouched from previous installments. If you've played any previous Mario Party game you know just what to expect from these bite sized games. Some have you doing basic platforming, some require pressing buttons with special timing, and some just require shaking the Wii remote like an idiot. The minigame offering is, as a whole, a lot stronger than what was seen in Mario Party 8. The games that rely on motion control are still kind of dodgy, but for the most part the minigames remain a fun and enjoyable component of the game, as always.
Unfortunately, Mario Party 9, perhaps more so than any other entry in the series, places a large emphasis on luck. The Mario Party series has always been known for game changing events where players can go from first to last solely based on the roll of the dice. Mario Party 9, however, seems to go out of its way to emphasize this more than ever. Every board contains events that can cause players to lose half of their Mini Stars, and these events pop up far more often than one may expect. It's pretty harsh. There are also still the requisite minigames that are purely luck based as well. Luck has always been a major component in the series, but it can feel particularly cheap in this installment, especially on the occasions that the game seems to turn against you and throw everything it can at you to keep you behind.
As always, Mario Party 9 becomes extremely tedious to play when playing in single player. The faster pace of the boards does at least mean that you spend less time watching CPU players take their turns. They still have a nasty habit of ganging up on the single player, though. Mario Party 9 really demands more than one player to fully be enjoyed. It still retains the frustrating luck-based elements of the previous games in the series, but the new style of play provides a welcome breath of fresh air. After a half-decade absence, Mario Party 9 brings the series back in fine form. If you've got some friends to party with, I recommend picking it up. If nothing else, you can at least get a laugh out of all the terrible puns used throughout the adventure!