No cheats, but hear is an easy way to unlock EVERYTHING!!!
You can wager koins with different profiles if each profile has at least one koin of each type. You can wager koins by pushing R at the character selection screen before choosing a character. In the game you can open a krypt only once and obtain that particular bonus. With different profiles you can open a particular krypt once per profile. Therefore tombs where you receive extra koins can be effectively utilized. For Instance Krypt FN yields 1800 jade koins for 93 Jade Koins. If you perform this once per profile you easily obtain 3600 Jade Koins and can unlock Raiden in Krypt XG. Remember there are no limits to the amount of profiles you can have. But write down the profile passwords so that you don't forget. Other important tombs include PK which yields 475 Platinum Koins for 157 Platinum Koins, UV which yields 520 Sapphire Koins for 256 Jade Koins, PD which yields 1056 Platinum koins for 451 Ruby Koins.