later in the game luigi gets his hammer and he hits Mario (like he has wanted too for years) and Mario shrinks and can go through tiny cavern like paths
same way you get marios.
use the hammer
You can get Beans, and an SP: Magic Window.
You can only do it with Mario and Luigi. For Mario, press A. For Luigi, press B.
no
not really
noone
You have to complete the pumpworks level
There are only 2 files in Mario and Luigi Bowser's Inside Story.
you have to hit the shell block.
on the map
By defeating him in battle.