Much of the removal in Modern Horizons is slow or clunky, so having a cheap, disruptive threat that synergizes super well with ninjas and blink while being outstanding by itself makes it a top tier common
There have not been any other recent new codes, unfortunately
It doesn't copy whether that creature has any counters on it or Auras and/or Equipment attached to it, or any non-copy effects that changed its power, toughness, types, color, and so on
That, though, is not the only reference to the under the table subgame in Unhinged
Packs What Are the Best Jump In
On the plus side, it also lets you proliferate: an effect that can be worth a few mana in itself depending on the board state