Play with 5 players in Battle Mode - You enter this code at the "START GAME" button in the wii channels screen.
It takes you to the controller arrangement screen.

Note: The Classic controller pugs into the wiimote rendering the wiimote useless so you can substitute any wiimote for a Classic controller in the below equation)
(You use 4 wiimotes and 1 GameCube, 3 wiimotes and 2 GameCube, and so on.) Once you are there arrange the controllers (by pressing any button) so there are 5 in the onscreen list. Then enjoy 5 player Battle matches!

Hold "R" on GameCube controller that's in slot 1 while you hit "START GAME" on the wii channels screen Access to controller arangement screen

Password: Result:

CBCCBBDB A-1
DDCDBBGB A-2
FFDDBBJB A-3
GHFDBCLB A-4
GJFDBCMB A-5
HKFDBCNB A-6
HLFDBCPB A-7
JNFDBCQB A-8
GCDDCCKB B-1
HFFFCCMB B-2
JGFFCCNB B-3
JHFFCCPB B-4
KKGFCCRB B-5
LLGFCCSB B-6
LMGFCCTB B-7
CKFFCHBC B-8
LFGFFCQB C-1
LGGFFCRB C-2
MHGFFCSB C-3
DFGFFHBC C-4
DGGFFHCC C-5
FHGFFJFC C-6
GKGFFJGC C-7
GLGFFJHC C-8
GBGFKJFC D-1
HDGFKJGC D-2
HFGFKJHC D-3
JGGFKJJC D-4
JHGFKJKC D-5
KKHFKJLC D-6
KLHFKJMC D-7
LMHFKJNC D-8
NFHFTJQC E-1
PGJFTJSC E-2
PHJFTJTC E-3
GFHFTDBD E-4
GGHFTDCD E-5
HHHFTDDD E-6
JKHGTDGD E-7
KLJGTDJD E-8
KCJGTJGD F-1
LDKGTJJD F-2
LFKGTJKD F-3
MHLGTJLD F-4
MJLGTHLD F-5
MKLGTJND F-6
NLLGTJPD F-7
QNMHTJSD F-8
JBLHTXBF G-1
KCMHTXDF G-2
KDMHTXFF G-3
LGNHTXHF G-4
MHNHTXJF G-5
MJNHTXKF G-6
NLPHTXLF G-7
NMPHTXMF G-8