cascade... wording...

[divine storm]

ok cascade says:
 "Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order)"

so my question is that it explicitly says "you may cast it without paying its mana cost" does that also give you the option of playing the spell and paying the mana cost. seems like the obvious answer is no, but the wording is not clear enough and there is no official wizzards ruling on this part.
the "may" is what is throwing me off, the "may" implies choice. so reading this i read it 2 possible ways. that you may choose weather or not to cast it for free, or that you may choose to cast it for free or not cast it at all (this being the general concensus).


fireball is a spell that can be cascaded if i do get this as my cascade spell can i *cast with* mana to make it deal damage?

and one more thing.. does the "without paying its cost" cover aditional costs like sacking land to harrow?

edit*

[Nefarias]

As for the first question, I'm fairly certain that what you list as the "general consensus" is correct, but I'm not 100% (only like 95%), so I'll let someone else answer that one for sure.

But as for your second question about Harrow, Cascade reads "without paying its mana cost." Sacrificing a land is not part of the mana cost, so it isn't covered by cascade. In other words, you would still have to sac the land.

[divine storm]

thank you very much. thats what i was told, but would be pissed if i went to a tourney and that wasnt the case.

[Clariax]

With cascade, you may "cast it without paying its mana cost."  You may choose to do that, or choose not to do that.  There is no "cast it, but pay the mana cost" option.