For what should be obvious legal reasons, you cant create MTG cards to sell or distribute since WotC own all rights to the cards artwork, either though first printing rights or full purchased rights (I think the former is the case)
Ideas for nonland mana sources are Grand Arbiter Augustin IV, Stormscape Familiar, signets and Chromatic Lantern
Selecting a card will provide more information on how the card style can be obtained: through bundles, seasonal rewards, play, or purchase through the deck builder
In the One Piece's OP13 'Carrying On His Will' English set, misprints spark opportunities, Demon Packs hide mythic villains, and even legends like Roger arent safe from production blunders
When you're willing to just duke it out on the battlefield it can be incredibly frustrating to have to look over at the Blue player's open mana and wonder if there's any point at all in casting the huge beastie that's been sitting in your hand for turn after turn