How on theme, nasty undead surrounded by diseased vermin.
This low cost mana and threshold deck works on two fronts.
Necro pumps out a skeleton each turn to bring your undead back.
Your spells such as Ghostfire, Second Wind and Murder of Crows have recursion to cast from the cemetery.
Gifts for the bump on your rats and undead, plus card draw.
Onslaught for that big hit turn.
Wolpertinger to take advantage of the dead rats that cant comeback.
Assorted Animals to go get Your 5 different named rats and Wolpertinger to put in your hand.
And finally, Ersatz Plats to help smooth any threshold issues, but your should be able to operate with only 4-5 sites as this deck tops out at 4 mana.
Just a fun theme deck!