The reason I think it works is because splitting up this cost is kind of difficult. Destroying an artifact is worth slightly less than

, but destroying a nonbasic land is worth just a little more than

(or is it worth just that much? if it is, this spell could be 1R entwine 1). This would mean it would be slightly undercosted for LD, and look even more like pillage. Pillage is an awesome card, and I don't want to make a new one.
Perhaps I can create a new mechanic here. One of the tricks design uses is placing targeting restrictions on cards. One such restriction is requiring all of a spells targets be legal before casting it. This means that they can make very powerful cards that only work in narrow situations (decimate, hex).
What if you could reduce this restriction by paying a cost?
Shockwave

Sorcery
Choose both of these - Destroy target artifact, and destroy target nonbasic land.
"unravel" - sacrifice a permanent. (When you play this spell, you may sacrifice a permanent. If you do, you may choose only one target).