Mario & Luigi: Partners in Time

I have a few tips.

1. Save up about 90 beans to buy the Ulti Free Badge from Fawfuls bean shop. This way, you can use as many bros items as you want and the stock stays the same.(If it works,there will be a -- symbol where the stock number is when battling enemies)

2. There are some questions already answered about strategies on how to beat Princess Shroob and her sister. You might get some help from looking at those.

3. To use mix flowers, you will need all 4 brothers(the 2 adults and the 2 babies). To actually use them, one brother will have a big fireball in his hand. Press that button repeatedly to make the huge fireball on top of the top screen bigger. It will also go higher. Soon, it will swap to another brother. Press his button repeatedly. Repeat to add damage until the fireball gets on the bottom screen. After it gets on the bottom screen, the fireball will do severe damage to all opponents.

For training, start in the main area of Shroob Castle, the place where you had to split up the bros. and hit the synchro blocks. As for the Mix Flower, use SuperiorAlex's instructions and cocentrate on hitting the right bros' button. One mis-press does a lot more damage than waiting a second to find the right bro.

First equip Mario and Luigi w/ supreme slacks or space trousers (both are pretty good)
Then equip the babies w/ 100-point pants or rocket pants (same as above)
Get Ulti-free, Dynamic, and Cure badges
Get 1-up supers, ultra drops, and max shrooms
To use mix flower it is similar to bro flower but there are four bros
Fight when ready.