My guess would be this:
Mishra's Facorty is a 2/2 artifact creature that counts as an
"Assembly Worker." I think what is what the creature would be.
I can't think of any other A.W.'s, so I would guess its not a legal
tribe card for any deck but you can play with "one" in any deck.
All the Opal's give the creature type on them so they would count
as a tribe card for whatever tribe name they mention.
Opal Archangel would be an: Angel tribe card
Opal Titan would be a: Giant tribe card
Opal Acrolith would be a: Guardian tribe card
and so on...........
Guardian is my next Tribe deck.
"idea's/submittions welcome."
A person can submit more than one entry. If it uses the same
tribe its probably not going to be the exact same thing. As far
as I'm concerned, a person can submit as many decks as they
would like. The person who submits the tribe first will probably
get more votes than someone who submitted a similiar deck
later in the contest though.
Hope that helps,
Caveman