In theory, with a Naban, Dean of Iteration on the battlefield, you only need half the number of blue mana symbols on the battlefield to make Master of Waves good (for example, in the worst-case scenario where you have just a Naban, Dean of Iteration and a Master of Waves, you'll still end up with 10 power across five bodies, which is a pretty reasonable deal for four mana, and if you throw just one other Wizard into the mix, things cat get out of hand really quickly when Master of Waves' enters-the-battlefield trigger is doubled)
2004-10-04 You can't pay life, just like any player at less than one life can't pay life
This is quite excellent, as whenever its controller attacks, they create a tapped and attacking 1/1 Human token for each opponent
If you dont cast the card, perhaps because you choose not to or because its a land card, it remains exiled
However, you must send all energies attached to it to your Lost Zone