Surprisingly good in the current Boomsday meta.
Splash down minions to go face as much as possible.
If the opponent tries to scupper you by playing out taunts such as spreading plague, then Curse + Voidcaller is yuor best friend (better than Mossy Horror)
Buff your minion health with Coldlight Seer and / or Gentle Megasaur, then flip with Voidcaller for big damage.
Play Murloc Warleader to buff the ATK of your minions, then flip with Voidcaller to get a free health buff as well as an ATK buff.
Flip twice (with both Voidcallers) for finisher (if you really want to watch the opponent insta-rage-quit :-D ).