Check out Quix with fast cards (especially in Death). Nightmare (fast with blast). Sha-Vi (fast sneak). Lira (fast ranged). And Naga Assassin (fast backfire). Pelacor Deceiver (fast flying backfire)... Of course it depends on card and summoner levels but Death with Quix can be brutal :)
Creeping ooze (neutral) with an additional slow can also pair up nicely with Quix because -2 speed makes everyone on opponents side slower :)