Suffocating Fumes

Creatures your opponents control get -1/-1 until end of turn.
Cycling {2} ({2}, Discard this card: Draw a card.)

Halimar Excavator

Whenever Halimar Excavator or another Ally you control enters, target player mills X cards, where X is the number of Allies you control.

Frantic Inventory

Draw a card, then draw cards equal to the number of cards named Frantic Inventory in your graveyard.

Thought Scour

Target player mills two cards.
Draw a card.

Essence Harvest

Target player loses X life and you gain X life, where X is the greatest power among creatures you control.

Kalastria Healer

Rally — Whenever Kalastria Healer or another Ally you control enters, each opponent loses 1 life and you gain 1 life.

Bojuka Brigand

Bojuka Brigand can't block.
Whenever Bojuka Brigand or another Ally you control enters, you may put a +1/+1 counter on Bojuka Brigand.

Lotus Petal

{T}, Sacrifice Lotus Petal: Add one mana of any color.

Changeling Outcast

Changeling (This card is every creature type.)
Changeling Outcast can't block and can't be blocked.

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Brainstorm

Draw three cards, then put two cards from your hand on top of your library in any order.

Mothdust Changeling

Changeling (This card is every creature type.)
Tap an untapped creature you control: Mothdust Changeling gains flying until end of turn.

Umara Raptor

Flying
Whenever Umara Raptor or another Ally you control enters, you may put a +1/+1 counter on Umara Raptor.