These codes are great to enter if there's a particular Strider level in the game you want to play.

Unlock Level 1:
Enter AAIA AAAA AAIA

Unlock Level 2:
Enter BCJB BBNB NBAB

Unlock Level 3:
Enter CEOC KCOC OCMC

Unlock Level 4:
Enter DGPD LDBD BDAD

Unlock Level 5:
Enter HLDJ PIGH GHCH

Unlock Level 6:
Enter HLDJ DIGH GHGH

Unlock Level 7:
Enter HLEJ DIGH GHHH

Unlock Level 8:
Enter INHK GJHI HILI

Unlock Level 9:
Enter JPIL HKIB IBMJ

Unlock Level 10:
Enter CJBE ADBO BONC

Unlock Level 11:
Enter BJAP PEAN ANOB

Unlock Level 12:
Enter DMCC BGCP CPOD