Defender
Approval — Political Prisoner can attack as though it didn't have defender as long as the number of colors among permanents you control is greater than the number of colors among permanents defending player controls.

Runway Mech enters with a +1/+1 counter on it.

Flash
Whenever you cast a spell during an opponent's turn, tap up to one target artifact or creature.

The first spell you cast each turn costs {2} less to cast.
The second spell you cast each turn can't be countered.
Whenever you cast your third spell each turn, draw a card.

Flying
Whenever Arsenal Mentor attacks, teach target attacking creature with lesser power flying.

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

When Barbarous Roughrider enters or leaves the battlefield, each opponent loses 2 life unless they sacrifice a nontoken creature.
Wander {4}{B}{B}

{1}{B}, Exile two permanent cards from your graveyard: Choose one —
• Create two 1/1 green Saproling creature tokens.
• Exile the top card of target opponent's library. You may play that card for as long as it remains exiled, and mana of any type can be spent to cast it.

Whenever a creature you control dies, each opponent loses 1 life and you gain 1 life.
{B}{B}, Exile Gilded Death and six other cards from your graveyard: Create a tapped token that's a copy of Gilded Death.

Whenever Inner Ring's Pupil enters or attacks, target player discards a card. If they can't, they sacrifice a creature. If they can't, they lose 7 life.

When Iris Cultist enters, you lose 1 life.
Cybersoul {4}{B}

During your turn, you may play cards from your graveyard but not from anywhere else.
Whenever you cast an instant or sorcery spell, exile that card instead of putting it into your graveyard as it resolves.
If another permanent you control would be put into your graveyard, exile it instead.

When Phyto's Offshoot enters, you may exile any number of permanent cards from your graveyard. When you do, target opponent reveals that many cards from their hand. You choose one of them. That player discards that card.
When Phyto's Offshoot leaves your graveyard, exile all cards from your opponents' graveyards.

Ward—Pay 3 life.
Whenever another creature you control dies, put your choice of counter from among lifelink, deathtouch, menace or +1/+1 on Sire of Bloodlines.

Flying
Favored
Whenever another legendary nontoken creature you control dies, you may exile it. If you do, create a token that's a copy of it, except it has no name, it isn't legendary, and it is a Zombie.

Decayed
You may cast The Venerable Veteran from your graveyard.

Lifelink
When Vibeseeker enters, scry 1.

Whenever another creature dies, if it had one or more counters on it, you may put one of those counters on Wicked Steed.

Menace
Cybersoul {3}{B}

Whenever you cast a spell, if mana from an artifact source was spent to cast it, you may copy that spell, and you may choose new targets for the copy. Do this only once each turn.

Menace
Creature tokens you control get +1/+1, have haste, and must attack each combat if able.
At the beginning of combat on your turn, create a 1/1 red Soldier creature token.

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}

When Firebrand Disciple enters, you may exile an instant or sorcery card from your graveyard. If you do, draw a card.

Haste
Whenever Penrath Firearm attacks, create a colorless Equipment artifact token with “Equipped creature gets +2/+0” and equip {2} attached to target attacking creature.

Flying, haste
When Plasmana Hellkite enters, it deals 2 damage to any target and 1 damage to any other target.