As The Mimeoplasm enters, you may exile two creature cards from graveyards. If you do, it enters as a copy of one of those cards with a number of additional +1/+1 counters on it equal to the power of the other card.
"He's an ugly little spud, isn't he?"
—Dr. Raymond Stantz
Treat The Mimeoplasm as though it were the creature card it's copying entering the battlefield. Any "As [this card] enters," "[This card] enters with," and "When [this card] enters" abilities of that creature card will work.
22-09-2011
wotc
You choose which one The Mimeoplasm is copying and which one determines how many +1/+1 counters are placed on The Mimeoplasm as The Mimeoplasm enters.
22-09-2011
wotc
Specifically, if The Mimeoplasm as a copy of a creature card that enters the battlefield with a number of +1/+1 counters, The Mimeoplasm will enter with those +1/+1 counters and +1/+1 counters equal to the power of the other exiled card.
22-09-2011
wotc
You can't choose to exile just one creature card.
22-09-2011
wotc
The two creature cards may come from the same graveyard or different graveyards.
Random a card of Magic: The Gathering (MTG), but you can also roll the D20 dice, random a Planeswalker, have fun with the random rules and more.