MTG Salvation

As an example:

bolas's citadel in play, lotus bloom on top of the library.

Can i pay 0 life to cast lotus bloom? Its CMC is 0, right?

Every card has a CMC; if it has no mana cost, its CMC is 0. You can pay 0 life to cast Lotus Bloom or any of the other suspend cards with no mana cost.

Yes that works. Bola's Citadel has you cast a spell using an alternative casting cost, so you can use that cost to cast Lotus Bloom.

cheers thanks.

I'd suspected that it worked, but i wasn't sure.