As an additional cost to cast artifact spells, you may pay {2}. When you do, each opponent sacrifices an untapped creature.

When Askir's Rearguard enters, if a creature you control dealt combat damage to a player this turn, draw a card.
Wander {1}{U}

Menace
Whenever you cast an artifact spell, each opponent loses 2 life.

Menace
When Askir enters, each opponent loses life equal to the amount of life they've lost this turn.
Wander—{1}{B}{B}, Pay 4 life.

Deathtouch
If an opponent would lose life, they lose that much life plus 1 instead.
Spellcharge 3

This spell can't be countered.
Haste
Whenever an opponent casts a spell during your turn or spends at least five mana to cast a spell, Aspirant's Bane deals 5 damage to that player.

Equipped creature gets +2/+0 and has reach.
Whenever a creature you control enters, if it wandered, you may attach Aspirant's Hookrope to it.
Equip {2}

Create a tapped 2/1 red Human Warrior creature token.
Flashback {2}{R}

Trample
Whenever Aspiring Anarchist attacks, you may have its base power and toughness become equal to the power and toughness of another target attacking creature until end of turn.

Haste
When Assault Engine enters, gain control of target creature and untap it. Sacrifice it at the beginning of the next end step.
Crew 2

Target creature gets +2/+0 until end of turn and must be blocked this turn if able.

Flying

Creatures you control get +1/+1 until end of turn.
Put a +1/+1 counter on each artifact creature you control.

Choose a creature type. Put a +1/+1 counter on each creature you control of the chosen type.
If you control two or more creatures that share a name, draw a card.

Choose any number —
• Each player sacrifices an enchantment.
• Each player sacrifices an artifact.
• Each player sacrifices a creature.

Choose one. If your devotion to white is three or greater, you may choose another. The same is true for devotion to black.
• Each opponent loses 4 life and you gain 4 life.
• Destroy all creatures with mana value 3 or less.
• Return up to two creature cards from your graveyard to your hand.

Indestructible
As long as your devotion to white and black is less than seven, Athreos isn't a creature.
Whenever a creature dies, exile it with a coin counter on it. Each opponent loses 1 life and you gain 1 life.
Whenever Athreos attacks, put a creature card you exiled with a coin counter on it onto the battlefield under your control.

Exile target nonland permanent.

Exile target creature.
Scry 1.

When Attuned District enters, scry 2.
Whenever you scry, you may pay {1}. If you do, create a 0/0 colorless Construct artifact creature token, then put X +1/+1 counters on it, where X is the number of cards you looked at.

When Audacious Roughrider enters or leaves the battlefield, exile the top card of your library. Then you may discard a card. If you do, put the exiled card into your hand. If you don't, create a Treasure token.
Wander {4}{R}{R}

Favored
Whenever a legendary creature you control attacks, create a tapped and attacking token that's a copy of that creature, except it's not legendary and is an enchantment in addition to its other types.

Whenever Augmented Ruffians attacks, integrate the top card of defending player's library.
Augmented Ruffians gets +1/+1 for each card integrated onto it.

Creatures you control get +1/+0.
Creatures you don't control get -1/-0.

{1}, Sacrifice Auto Sifter: Search your library for a basic land card, reveal it, put it into your hand, the shuffle.