Murder at Castle Nathria Cards List & Guide
Deal 4 damage toall minions. Give youropponent an AbyssalCurse.
Often followed up with a chasmic handshake.
Mistermath's Card Ratings for Voyage to the Sunken City:
Using the 2.5 estimate, this is very similar to a Felfire Potion, with the upside that you don't take 5 damage yourself and the downside of dealing 1 less damage to all minions. Seeing as Felfire Potion was a fair card that pretty much set the default for 6 mana boardclears, I'm willing to give this card the exact average rating of 5/10 as well.
This card is bad. It should deal 1 more damage or cost 1 less mana.
Nice, basically a Soul Rend with Curse of Rafaam