See Challenge # 108.

Giant death-ray! I debated using a reprint, maybe vindicate or heat ray, or even murder or lightning bolt. But I wanted something that exactly captured that feel of "awesome". Also it didn't look like it was firing down on a planet. So here's an X-damage-to-player spell that also has a battlefield-affecting effect.

Oh, very nice. It's not better than Fireball, but I'd run it over the ball on occasion anyway, since the occasion when it's the right tool sounds awesome.

Thank you. Yeah, there's a lot of XR spells with slight advantages over each other, it's hard to find a sweet spot. I think is is usually worse because "x to creature" is usually more useful than "1 to all creatures", but it will sometimes be the right choice, and any x spell is good if it's the only one in the environment.

The X=0 case is actually more efficient than has been printed - it's an overloaded Electrickery for 1 mana not 2. And I think that's the way to think of it: an Electrickery or one-sided Tremor with a kicker to burn the player. Of course, don't think of it exclusively like that or you'll miss the occasional chances to kill the opponent with it :)