The ideas of this deck are:
Play a lot of units to stall until you can cast Witching Hour
Play a lot of deadly units with Waxing Moon
Play Pale Riders Time Peace with free Spellcraft
Board wipe with a deadly Black-Sky Harbinger
Since I saw Waxing Moon and started testing it, I REALLY like the card. Having two is very strong as long as you play one on the following turn, then you ALWAYS have deadly units, and you will ALWAYS draw an additional card. This feels very good for any style of shadow deck. Don't tell mono shadow players about it though.