ok this secret is very cool an i think very little known.

for this secret you have to be snake and you have to be on the stage Shadow Moses Island and preferably in a brawl (not classic/allstar). To do the secret you have to be using the nunchuck and wii remote (im not sure if its possible w/wii remote/gc controller/classic) so start a brawl as snake on SMI and press the buttons 1+2 to do the taunt where you go into a box. well sometimes snake will kneel down and put his hand on his ear for about 5 seconds and then get up. after he gets up he will get a call that will show up on the whole screen much like the resetti assist trophy. Then Otacon will give Snake intel about his opponent then end the call. it doesnt sound cool but it is just try it. if you want to hear it for your self ive made a flipnote with the audio from brawl.

Snake and Otacon about Samus
the command for command search is:
→↓RL←R←Y↓Y

You can also do this with Fox, Falco, and Wolf. For Fox and Falco you must be on the stage Corneria (its a melee stage) for Wolf you must be on the stage Lylatt Cruise (wolf's takes a while be patient)

Fox, Peppy, and Slippy about the Brawl
flipnote with fox/falco's in command search:
RYBL→↓Y→RY

the easiest way to do this is to make a two player brawl with no one on the second player remote and first player snake. Alternatley, brawl against a level 1.

My awesome stop motion yoshi kart flipnote command:
RYA↑↓→BAYR
check it out if you have some time

Thank You for reading