All right, this technically requires a few Forests in play as well to work, but I think that’s probably manageable.

Turn the 1-drop into a Scryb Ranger and pick up a Forest to untap Vannifar. Turn the Scryb Ranger into a Renegade Rallier, return Scryb Ranger to play, and untap Vannifar again.
Turn Ranger into Bounding Krasis and (you guessed it) untap Vannifar.
Turn the Rallier into Restoration Angel and blink Bounding Krasis for one last untap.
Turn Resto into the Goblin, copy Krasis infinite times, and attack your opponent with infinite Fish Lizards.
Vannifar + 2- to 5-drop
This doesn’t require any Forests, but involves a bit more searching than the other. Pretend you’re starting with a 2-drop, and for anything above just skip ahead.

Turn the 2-drop into Bounding Krasis and untap Vannifar.
Turn the Krasis into Breaching Hippocamp (can’t use Restoration Angel here because then Vannifar has summoning sickness upon returning to play) and untap Vannifar.
Turn Hippocamp into Zealous Conscripts and untap Vannifar.
Turn Conscripts into Woodland Bellower and fetch up a Krasis to untap Vannifar.
Turn the Krasis into a Restoration Angel, blinking Bellower and untapping Vannifar.
Turn Resto into the Mirror Breaker and copy Bellower, fetching up a third Krasis, untapping your Goblin, and making infinity Fishies.