In Super Smash Bros. Brawl for the Wii, there are six hidden assist trophies you can unlock.
Ray MK3 Assist Trophy – Play 100 brawls
Isaac Assist Trophy – Play 200 brawls
Advance Wars Assist Trophy – Play 300 brawls
Barbara Assist Trophy – Unlock 25 or more CD’s
Shadow the Hedgehog Assist Trophy – Unlock Sonic the Hedgehog
Gray Fox Assist Trophy – Unlock Snake