If the rule you're querying is from a source other than the PRD (in this case Mythic Origins), it's a good idea to either link to it or copy/paste it into a thread like this, so that we can actually see what ability you're referencing. This lets us answer much more easily and quickly.
Also, bumping on a frequent basis is considered bad form (though not actually against the rules of the forum).
And, finally, I agree with FractalLaw. All it requires is is for the Target line of the spell to affect a specified number of creatures (any specified number, so "all creatures in a 20 foot radius burst" doesn't count, but "one creature touched" is perfectly valid).
Thanks for the etiquette pointers; I should have linked the part on pathfindersrd.com. Sorry about the bumping.