Someone told me that Ulamog's Crusher is "Unplayable in Modern".... Am I missing something? It's not banned by wizards and in a tron deck which is what I have it in I can easily play it turn 4. So does anyone know why someone said this?
This happened on a forum and when I asked why I was never responded to. Just wondering if there was something that I'm supposed to know that I don't.

"Unplayable if you want to be highly competitive" perhaps would be more correct. In competitive modern there are just better bombs available for Tron: Wurmcoil Engine, Karn Liberated, Ugin, the Spirit Dragon, and Ulamog, the Ceaseless Hunger. For a budget build Ulamog's Crusher is just fine, but a colorless 7 drop would probably be better since it's possible to drop one on turn 3. Maybe Bane of Bala Ged.

Ok that makes sense. Except for Karn I have all the cards you mentioned in the deck as well. I should probably check my quantities though. Thanks.