Hired Poisoner

Midnight Assassin

Flying
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Bloodline Pretender

Changeling (This card is every creature type.)
As Bloodline Pretender enters, choose a creature type.
Whenever another creature you control of the chosen type enters, put a +1/+1 counter on Bloodline Pretender.

Changeling Outcast

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

Guildsworn Prowler

Deathtouch
When Guildsworn Prowler dies, if it wasn't blocking, draw a card.

Aven Heartstabber

Flying
As long as there are five or more mana values among cards in your graveyard, Aven Heartstabber gets +2/+2 and has deathtouch.
When Aven Heartstabber dies, mill two cards, then draw a card.

Mistwalker

Changeling (This card is every creature type.)
Flying
{1}{U}: Mistwalker gets +1/-1 until end of turn.

Etrata, Deadly Fugitive

Deathtouch
Face-down creatures you control have "{2}{U}{B}: Turn this creature face up. If you can't, exile it, then you may cast the exiled card without paying its mana cost."
Whenever an Assassin you control deals combat damage to an opponent, cloak the top card of that player's library.

Big Game Hunter

When Big Game Hunter enters, destroy target creature with power 4 or greater. It can't be regenerated.
Madness {B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)