As those who've played it know, Mario & Luigi Dream Team is not a simple game. With brutal boss fights that can rip players to shreds, difficult enemies and rather low stats for the player characters, the game is by far the most difficult in the series, with some rather annoying puzzles making even more aggravating to boot.
But here are some tips that'll help you get through the game (more precisely, the endgame) more easily. Yes there are spoilers here, but come on, guides always contain them, especially ones like this.
1. Use the Wellington Boots to farm Beans
First things first, here's a really nice tip for farming beans in the game without going through the hassle of hunting down the 'fixed' ones across the kingdom or defeating Gold Beanies en mass.
Basically, a later item a certain enemy in the last dungeon drops is called the Wellington Boots. You know, those things you use to go through mud/water in the real world.
What do they do?
Make it so enemies have a chance of dropping a bean instead of money when defeated via a jump attack.
So what you need to do is equip them on Mario, go to a dream world from very early in the game (Pi'illow Castle, Mushrise Woods or Dozing Sands would be perfect here), then stomp on an enemy for a first attack.
You see, in the dream world, enemies don't come alone, they come in large groups of about ten or more. If you use a first strike against a weak group... well, that's ten or so down from a single jump attack, and about a 80% chance of getting at least one permanent stat boosting bean out of the process.
Just repeat this til you get tons of them, then curb stomp the final bosses and Battle Ring. Or grind until your stats reach 999 everything* if you're bored enough, then basically smash everything into powder on contact with your might boots of instant death. Either way, god like Mario and Luigi!
* May take about two weeks of grinding if unlucky.
2. Use the Gold Hammer/Gold Items to turn your coins into power
Another interesting tip to boost your hammer attack power or things is simple; use the Gold items.
What do these do you may ask?
Increase your attack power based on the amount of money you have.
And this game literally chucks coins and money at you non stop, so doing this lets you wipe out even the toughest enemies with a single jump/hammer blow.
Of course, you'll need 600 challenge points to get the Gold Hammer... so good luck with that bit.
3. Solving Kamek's Door Woes in Bowser's Castle
In the last dungeon (Neo Bowser Castle), one of the first puzzles you encounter is Kamek using an annoying magic spell to randomise where the doors send you. Sort of like the Lost Woods from the Zelda series or Big Boo Battle from Mario 64 DS, except with a far less complex pattern.
But what the game never hints at (and trust me, you can very easily miss this), is that only ONE, very specific door leads to a room you need to progress.
So which door? How to proceed?
Go through the north door in the first room, then go through the top most door on the left side. You've basically then solved the 'puzzle', since the other doors here lead to the areas you need to hit the switch and access the dream world. Hope that helps.
4. The Answer to the Zeekeeper's Forest Maze
Another 'maze' like puzzle area you'll encounter is a tree/forest maze required to reach the Zeekeeper's egg in the dream version of Somnom Woods. If you go right from the portal, you'll find that all doors lead you to either a blocked passageway or the same area.
Go LEFT from the portal you enter from to find a secret passage leading to a new room.
In here, you find ANOTHER maze. This is... clever. Basically, don't go left. If you do, you hear a 'buzz' type sound indicating you failed and the room loops you back to its entrance. Similarly, don't just go straight to the right, otherwise the same thing happens. Instead, watch the coins, and take the paths marked by the money to successfully solve the 'maze' and reach the next area.
It's much easier to figure out from there on.
5. Surviving the Giant Bowser Battle
Yes, it's a pretty big spoiler knowing that Giant Bowser is one of the giant bosses you fight as Dreamy Luigi in this game. But trust me here, you NEED to know these important tips for the fight in order to survive.
First things first, use the Hammer Uppercut when you start to knock him back. Really, don't use ANY other move as your first move.
Why? Because when you do, Luigi moves a bit to the left to battle him. And then, the Shy Guy Brigade will basically blow part of the bridge to kingdom come.
If Luigi is still standing at the start point, well his rear end meets the lava. And it costs him about a quarter of his health bar. So use the Hammer Uppercut as your first attack at all costs!
Secondly, when Bowser charges at you... he charges to the left or right, not head on. Go the OTHER way by dodging. I completely missed this cue the first few times, and I paid dearly for it.
It's not much, but these two tips will save you making the same mistakes I did the first time around.
6. Finding the way out of Antasma's Nightmare
In the last Antasma battle, one of its 'interesting' attacks is to put Mario to sleep and chase him through what's basically a nightmare within the dream world, with different holes in the floor that leads to side scrolling falling sections with spikes and obstacles.
But while at first you might think this is entirely luck based (pick the right exit or keep using trial and error to find the one with a glowing background and generous healing items), it's actually not.
No, what you need to do is to jump OVER the holes. The right one wil then get a red outline, showing you which one you need to enter to leave the nightmare.
Hope that helps!
7. Making Pi'illodium Easier to Defeat
Finally, a boss you may have massive trouble defeating is Pi'illodium, the mysterious guardian on the Pi'illow Temple. This robot creature will fly around, shoot lasers and missiles at almost machine gun speeds and use all kinds of near undodgeable attacks in its attempts to kill the Mario Bros.
It also speaks like the Robo Peach Castle from the last game or the Daleks/Cybermen from Doctor Who, saying things like 'Chance of my victory: 120%' and stuff about your speed is slow/offences are weak.
But there's a nice way to make it much, much easier to destroy. Get rid of its wings first.
Yeah, just hit them with some Bros Attacks so they crack, and you'll ground the boss. This will also change its facial expression, lower both its attack and defence and open it up to ground based attacks like your hammer or shells.
And hey, it doesn't do that cheap attack where it turns into a hammer off screen any more! Or charge you from the background while firing a torrent of missiles!
I hope those tips help, and some more will be added later.