MScore: 4.7/10
Nascent Metamorph
Creature — Shapeshifterrare
Whenever this creature attacks or blocks, target opponent reveals cards from the top of their library until they reveal a creature card. This creature becomes a copy of that card until end of turn. Then that player puts all cards revealed this way on the bottom of their library in a random order.
1/1
Illustrated by Brian Valeza · Commander 2020 · #36
Rulings for Nascent Metamorph
6
2020-04-17
The creature card that Nascent Metamorph becomes a copy of is put onto the bottom of the library along with any other cards.
2020-04-17
If the target opponent has no creature cards in their library, Nascent Metamorph doesn't become a copy of anything. The cards are returned to that library in a random order.
2020-04-17
If another permanent becomes a copy of Nascent Metamorph, it will become whatever Nascent Metamorph is copying. It remains a copy when Nascent Metamorph's effect ends.
2020-04-17
If an effect begins to apply to Nascent Metamorph before it becomes a copy, that effect will continue to apply.
2020-04-17
If Nascent Metamorph becomes a copy of a legendary card with the same name as a legendary permanent you control, you'll put one of them into its owner's graveyard.
2020-04-17
If Nascent Metamorph becomes a copy of an object with a set of linked abilities (for example, one ability that exiles a card and another that refers to the card "exiled with" the object), that link only lasts as long as Nascent Metamorph is copying that object. If it stops being a copy of that object and then becomes a copy again later, the link is lost.
(You may pay an additional 
, Sacrifice X Clues: Target opponent reveals the top X cards of their library. You may put a nonland permanent card with mana value X or less from among them onto the battlefield under your control. That player puts the rest on the bottom of their library in a random order.