That Mario is one charming son of a bitch. He's so damned charming that he can beat you with a hammer for 16 hours worth of Mario & Luigi: Partners In Time (for the Nintendo DS) and then convince you that you had fun at the end. You'll walk away thinking how much you love him, and when people ask you what happened to your face you'll tell them you walked into a door.
Because Partners In Time isn't a good game. It's repetitive, it's unoriginal, and the controls are intensely annoying. But there's just something about it that will keep you grinnning stupidly to yourself as it starts to viciously work your kidneys.
Mario's never been long on story, but Partners In Time makes an effort. When a local boffin invents a time-travel machine, Princess Peach is the first to test it, and soon she's predictably lost in the Mushroom Kingdom's past and squealing like the whiny child she is. Enter Mario and Luigi, who promptly hop back into history to save her. They soon find that the past is under attack by evil mushroom aliens called Shroobs, and in order to combat this threat they enter an unlikely team-up with their 3-year-old baby selves.
The game essentially plays as a platformer/RPG hybrid, in the style of the Mario RPG and Paper Mario games. You'll wander through isometric platform-stewn levels, bopping blocks and pushing switches and the like, but when you make contact with an enemy it's all turn-based, and you and your foe take turns bouncing on each others' heads.
The RPG elements are thinner than Mary Kate Olsen. You gain experience and level up in a fairly linear fashion. You can change your pants (the only form of armour or gear in the game), and you can equip badges to gain situation-based advantages. You can only have one badge per character, though, and there's not really much depth or strategy in deciding what to wear.
In combat the focus is less on your stats and more on your reaction times. Each attack requires some variety of button-pressing minigame to maximise your damage, and incoming enemy blows can be minimised or dodged by jumping or swinging your hammer at the right moment. You'll need to escape roughly two out of every three enemy attacks, so mastering the (incredibly annoying) timing is key.
Outside of combat, each of the four brothers (two adults and two babies) is assigned to one of the four DS face butttons. You select a set of actions with the shoulder buttons, and then perform the action by pressing the relevant brother's button. You can move all four brothers together by piggybacking the babies on the adults, or you can split them into teams of babies and brothers, who can move separately.
Games where you need to independently control two different teams have a long and convoluted history of punching nuns, and Partners In Time is no exception. No one likes cutting their combat effectiveness in half, not least because brothers not present in combat don't gain XP. "Teamwork puzzles" is a phrase game developers use as code for "I have a shrine to Hitler in my basement." It won't take you long to realise that this would have been a vastly better game if the "adults and babies" gimmick were missing completely.
Speaking of which, the "time travelling" scenario really only extends as far as introducing baby characters. You're only going to one time period (the past), and it's not like anything you do there changes or affects the future. You'll want to kick Luigi in the face for having apparently solved all the puzzles as a baby, and then forgotten the solution by the time it comes to do it as an adult.
The game's not long by videogame standards (the 16 hours mentioned above), but that's still about eight hours of padding. Each level is about twice as long as feels right, stretched out with extra switch puzzles and jumping sequences (which are, incidentally, incredibly easy). The pacing just feels completely wrong, and there's a good chance that if the game had been shorter and tighter I wouldn't have had time to be annoyed with its many flaws.
For all the above criticisms, Partners In Time is a game with a lot of soul. The story sequences wring a lot of value out of a small number of animations for the brothers, and both the visuals and the limited snippets of Mario-style speech really bring the Mushroom Kingdom to life. There are even a few laugh-out-loud moments to be found.
If you want a Mario RPG, you'd be better served by almost any other Mario RPG ever made. But if you somehow end up with this one, you probably won't regret it too much. After all, Mario is really a great guy - he just has trouble controlling his temper sometimes.