+, and can only target basic (though clearly you'd want to, assuming you fixed it, since right now the type 'basic land' kinda makes it redundant...)

Seems overly nasty, for something that probably won't deal much damage. I guess combining it with some form of Armageddon would make this an evil finisher. Still, I think restricting it to basic only is over the top. Why not let someone use it to kill an evil land in a pinch?

Vitenka, I'm not sure what you mean by "overly nasty" in the above comment, as this is just a weaker version of Roiling Terrain, and you seem to recognize that this is weaker too.

@Sorrow - Note that Roiling Terrain avoids using a variable in its rules text, as variables add an almost subliminal degree of complexity that is best avoided when possible.

The drawback seems overly harsh, is what I mean.