Let's say Maro or Overbeing of Myth are in my graveyard and I have 5 cards in my hand. If I were to cast The Mimeoplasm exiling Maro and another creature (lets' say Squire), and I wanted Mimeoplasm to copy the Squire and come into play with +1/+1 counters equal to the power of Maro, would the Plasm get 5 counters or 0? I know Maro's power and toughness are always checking my hand, even when in the grave - this is a CDA or card defining attribute, I think - I just don't know if that also allows Mimeoplasm to work the way i want it to.
Plasm gets 5 counters.
As you suspected, Maro's P/T is a CDA, and Maro is in the exile zone.
400.1. (...) There are normally seven zones: library, hand, battlefield, graveyard, stack, exile, and command. (...)
604.3. Some static abilities are characteristic-defining abilities. (...) Characteristic-defining abilities function in all zones.(...)
...assuming you actually have 5 cards in hand when Plasm resolves.
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As you suspected, Maro's P/T is a CDA, and Maro is in the exile zone.
604.3. Some static abilities are characteristic-defining abilities. (...) Characteristic-defining abilities function in all zones.(...)
...assuming you actually have 5 cards in hand when Plasm resolves.
RULES OF MAGIC :
http://magic.wizards.com/en/game-info/gameplay/rules-and-formats/rules