Pretty big upgrade on Electrostatic Bolt, which couldn't hit players at all.

For what it's worth, common burn spells don't tend to have a condition (upgrade or restriction) and also a new keyword ability. In a real set I'd expect there to be one burn spell with the Electrostatic Bolt wording, and another with the new keyword Loop.

Well, that is, if Loop made it through development. A keyword ability that encourages repetitive gameplay is unlikely to be popular. A keyword ability that uses shuffling every turn - maybe multiple times per turn - is very unlikely to make it to print because in tournament games a shuffle is a serious thing that takes up significant time; having just one common causing repeated shuffles would be a red flag, let alone a whole keyword ability's worth of them. That bit at least is really fixed by just putting the lands on the bottom of the library.

There's also the issue that Loop encourages players to give up their lands. I think this will lead to players mana-screwing themselves as they try to survive, making it less likely that they'll ever get to cast their big spells. This offers players a choice that they might regret for the rest of the game. Repeatedly, in fact.

In fact, this is a press-your-luck mechanic. Which is a direction Magic hasn't gone before, I think; and one I'm not personally keen to see; but I suppose there might be an audience for it? Probably not at common though unless the whole set is clearly marketed in that vein?