This is a 4-color hyper-aggressive Zoo style deck using Elementalist to power out minions turn after turn!

(As I test it, I will make changes.)

Auras / Artifacts

Minions

Bosk Troll / Autumn Unicorn - Big Beefy Beaters!
Scorpions / Corpses - Lethal threats that can trade up
Sinterfee - Use them to slow your opponent down
Vile Imp - An aggressive 2-for-1 creature that can also be used as the final points of burn with a summoning sphere.
Wild Fanatic / Warhorse - It has charge!
Corruptor Freak / Orm Infestor - These can prove to be MAJOR headaches for your opponent.
Root Spider - great to defend yourself, or to get in with later!
Clamor of Harpies - Take out a chump blocker then go on the offensive!
Daperyll Vampire - A very solid minion.

Magic

Finally:

ONSLAUGHT! This card is a FLOOD of damage, it can get your opponent to death's door in a flash!

Sites

Common Village, Open Mausoleum, ETC. - These are here so you can do your best Necromancer impression later in the game when your avatar is just drawing and playing sites, making your Onslaughts even better!
The towers and Ghost town - They make 2 mana, giving you a fast start!
Sinkhole - Blow up a problem land!
Primordial Spring, drawing 3 sites seems great!

Collection

Joven's Onslaught Elementalist