Mill and discard your own and opponents' decks, and pick the best to exile for the general. High power creatures with drawbacks are exiled for the +1/+1 counters, and lower power creatures with great abilities (e.g. indestructability) are the copy to lay the foundation.
http://tappedout.net/mtg-decks/mimeoplasm-discard-edh/
Mill and discard your own and opponents' decks, and pick the best to exile for the general. High power creatures with drawbacks are exiled for the +1/+1 counters, and lower power creatures with great abilities (e.g. indestructability) are the copy to lay the foundation.