Alternate ink color - During the introduction, press L or R to change the color of the ink you use to scribble on the bottom screen (with the Jump Pirate face). The initial color is white; the other colors are black, pink, blue, cyan, green, yellow/orangish, red, and gray.
Alternate training mode blocks - While starting Training mode through the deck maker, hold Up or Down to change it to a knowledge character or Left or Right to change it to a laughter character.
Komas - The following are Komas that can be unlocked from doing something other than beating J-Adventure mode missions. The easiest way to get the "Battle [number] times" Komas is to repeatedly fail the "get hit once and you lose" missions in J-Adventure mode.
Resisting harmful items - When you break open a crate, barrel, or any other object that makes items pop up, immediately hold Guard. All harmful items, such as the weight or poison, will land on you and disappear without any effect. This also works on helpful items; it works on everything except for bombs.