The amount of Mana you need can be more complex, depending on how you split your Colors, but the game has cards that give Mana for more than one color
Bello, Bard of the Brambles is a Gruul (red-green) legend from Bloomburrow that encourages players to pack their decks with as many cheap ramp spells and expensive artifacts and enchantments as they can, in large part because of his powerful static ability: during your turn, every 4 cost of greater non-Aura enchantment and non-Equipment artifact becomes an indestructible, hasty 4/4 Elemental creature, ready to smash face
They require you to go five turns without taking damage (or proliferate their filibuster counters), but there are many ways in blue and white that can keep you clear from danger, like Magus of the Moat, fogs, and Ghostly Prison effects
There are some cool ideas like the many ways of giving it deathtouch but thats a discussion for another time
#10 What about Nokho
Because this card has all lands enter untapped, The Wandering Minstrel can save you money when assembling a five-color mana base, which can get very pricey if you want a lot of fast mana