I currently run the Clever Impersonator, and it and
Phyrexian Metamorph (and
Cackling Counterpart/
Quasiduplicate) are primarily drafted/maindecked to copy the following (In descending order of prevalence):
- A Merfolk lord (Like ~60% of maindeck clones go in Fish, and the necessary density of lords'n'clones in that deck is why I'm after a 4th)
-
Proteus Staff or a creature cheated out with Proteus Staff
- A cost reducer like
Goblin Electromancer in
Sentinel Tower/
Aetherflux Reservoir decks (Mostly P. Metamorph and Quasiduplicate, the cost difference is real)
The primary targets in actual games are (In descending order of prevalence)
- A Merfolk lord
- Whatever BS the opponent just cheated into play
- Whatever decent midrange threat the opponent just cast
- Proteus Staff/literally whatever so we can start to use Proteus Staff
- A decent blocker or cost reducer in Storm
The only planeswalkers I run are the Origins flipwalkers (With Garruk Relentless over Nissa, Vastwood Seer) and Saheeli, Sublime Artificer, so Clever Impersonator doesn't really have that mode as an upside over the new Metamorph. It has copied opposing creatures a whole bunch in the Proteus Staff deck, so that's a major upside - but Hulking Metamorph is a better
hit off the staff and is still a castable-ish starting creature if push comes to shove. Impersonator
has copied an opponent's
Shark Typhoon and once an opponents
Astral Slide which were neat I guess, but it's more often been a dud polymorph hit.
Mythos of Illuna gets all the upsides of Impersonator, is never a dud hit off Proteus Staff, and easily has the best art, but if it copies a creature it dies to Astral Slide/other flicker effects (Eh, so do the Counterpart and Quasiduplicate and they perform just fine) and I don't really like the
trinket text even though there's enough fixing in my format to have it get used (it's
mostly a Fish card that also supports Polymorph, and neither of those produce
reliably so it might lead people to skip over it in the decks that want it, or pick it up for decks it's not great in).