This is a guide on unlocking all 12 secret characters and secret stages for Super Smash Bros for 3DS.
There are specific conditions for unlocking each character in Classic Mode. However, these are not fully known yet. The easiest way to unlock all characters is to simply play 120 matches. A character gets unlocked every ten matches.
The characters are unlocked in this order:
10 matches – Ness
20 matches – Falco
30 matches – Wario
40 matches – Lucina
50 matches – Dark Pit
60 matches – Dr Mario
70 matches – R.O.B.
80 matches – Ganondorf
90 matches – Mr Game & Watch
100 matches – Bowser Jr
110 matches – Duck Hunt
120 matches – Jigglypuff
If you want to speed up the pace you unlock these characters, you can rush through those 120 matches by playing a small stage, such as Final Destination, choosing a character that falls quickly, like Fox, and purposely killing yourself by falling off.
These are the conditions to unlocking several stages. You will also need to unlock the second Challenge panel:
Balloon Fight – use the Villager in three matches.
Dream Land – use Kirby’s Final Smash.
Mute City – use Captain Falcon in three matches.
Pac-Maze – use Pac-Man’s Final Smash.
Magicant – unlock Ness.
WarioWare, Inc – unlock Wario.
Flat Zone 2 – unlock Mr. Game & Watch.