Buster
"wahwahwah weeeeeooOOOooooooOOOOOO"
Translation:
This character has a Gain meter that goes up when hitting opponents and down when being hit. When the meter is halfway full, land NSpecial to access Overdrive.
During Overdrive, press the special button when you hit enemies with certain attacks to create an additional explosion. (Your character will flash white with applicable attacks)
Specials are self-explanatory but check munophone in practice mode if you need additional details.