The following are known Action Replay Codes for Metal Slug 7 on Nintendo DS (NDS).
Game ID: YM7E-66BDC88E
Invincibility
220f7c78 0000005f
Infinite Lives
220f7ef7 000000ff
220f7ef8 000000ff
Infinite Primary Ammo
120f7cb4 0000ffff
Infinite Secondary Ammo...