­Burden of Guilt says this can be cheaper.

...how the hell do you do that? You just have the entire oracle database memorized or something? Wahaha. Alright, will change.

And burden of guilt isn't even rated that highly. Haha.

Yeah, Alex pretty much has magic memorised.

White Sleep. Purists will of course get mad that it hits nonartifact creatures.

I bet wizards would think thrice about 'white sleep' because it is so backbreakingly effective against midrange for aggro decks, and midrange is exactly the deck that normally deals with aggro.

But, this set isn't really meant for that, so, sure.

Making this an instant while removing the "don't untap" clause will make this nearly the same but fit far nicer into the color pie.

The uses are very different. Sleep is very powerful because it allows two full attacks against the opponent. The Sleep / frost ability is primarily blue can bleed in white with Entangling Trap and Kor Hookmaster.

Let me see if I can differentiate this a bit more. I wonder what a sorcery called "Lockdown" can do? I originally tried something like "Creatures target player can't block this turn and don't untap during their controller's next untap step" until I realized that it was strictly worse than the pure white Sleep. haha.

You could make it a detain-esque effect.

Or you could make it red and instant and have its effect be creatures target player controls can't block or attack this turn.

Before:

Lockdown
Sorcery [u]
Tap all creatures target player controls. Those creatures don't untap during that player's next untap step.

Almost functionally the same, but within red and white flavor. whtie = can't attack, red = can't block.