While decks normally go in Strategy, I was also told people playing BETA should post BETA topics here in Test Server. Not sure where to put this, I put it here so apologies if in the wrong area.

The deck I have:

4x Twilight Opportunist
4x Demetreyo, Twilight Extremist
3x Twilight Ritualist
4x Phoenix Urigon

4x Road Less Traveled
4x Tome of Knowledge
4x Fireball
4x Supernova

4x Boooomerang
4x Ritualist's Headdress

Thinking of tweaking this, it has potential to me and I don't just say that because it is the first deck I have won with in the BETA. 2-2 so far, almost forced a Praxix to a draw but botched my last turn card play.

RLT is VERY good with Twilight allies and getting rid of opponent enchantments on my allies.
Phoenix Urigon, not sure how useful it is so far here, only 1-2 times did it come back blazing in a way I could use it. Considering replacing it with the low cost Herald from DP because of the tricks I can do with Twilight and greater ability to play+boost Demetreyo and other allies.
Might drop 1 Supernova for something.
Considering going a bit above 40 cards with a few Static Shock to help finish off 5 health allies I see opponents using.
Used Headress ability once so far, nicely done with Twilight before one of them self-kills itself.

Overall, I think this is a decent starting point for Nish, I built this when looking at Twilight and remembering ally-less Nish decks from back in the CotC days. The idea is to hit hard and fast, I have managed one game to come back from being beaten down to 8 health due to card draw luck. Weaknesses I can think of, lack of cc4+ item destruction and healing.