My favorites are Sandstorm Multi, Emeralds and Play Cyclone
Since double strike and "can't be blocked" are phrases we've seen time and again on Magic cards, I added the words to help my coworkers become familiar with what I was going for
In fact, we want it enough that Cornered by Black Mage is basically a two-for-one play, like a black mage Nekrataal
Ob Nixilis, the Hate-Twisted fits this list better but should be treated more like a 5-mana removal spell with upside, or a more costly Underworld Dreams that is a different type of permanent
Bubble Snare, Capture Sphere, Castaways Despair, Charmed Sleep, Claustrophobia, and others usually cost three or four mana, and tap down a creature and keep it tapped down
Wizards of the Coast (WotC) has a foil problem