MUC (Mono-Blue Control) is one of the oldest running archetypes in Legacy, and even the history of Magic. Blue has a lot of strengths, but undeniably it's largest are drawing cards and countering spells. The deck is built around a simple game plan: Counter everything your opponents play, and draw lots of cards so you have more counters than they have spells. Once you establish total control, you will drop a way to close out the game. There is a variety of ways to do this, but the most common nowadays is easily playing Jace, the Mind Sculptor.