nadu is going to get banned in most formats, this much we know. my sincere hope is that it gets banned in brawl, not just as a commander but in the 99 as well. and also a team is hired to track down every copy released in paper or digital and destroy it with fire, or perhaps acids.
nadu gives all your creatures "target me and draw a card, if it's a land it goes on the battlefield untapped" and that activates 2x each turn, for each creature you control. 0-cost targeters like Shuko, plus creature-creators like Scute Swarm (each creature created is 2 more free activations)