Tsagan, Raider Warlord

Double strike
Start your engines!
Whenever Tsagan attacks, creatures you control get +1/+0 until end of turn for each creature you control with first strike or double strike.
Max speed — Tsagan has deathtouch. Other creatures you control have first strike.

Prosperous Bandit

Offspring {1} (You may pay an additional {1} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
First strike
Whenever this creature deals combat damage to a player, create that many tapped Treasure tokens.

Silverquill Lecturer

Creature spells you cast have demonstrate. (Whenever you cast a creature spell, you may copy it. If you do, choose an opponent to also copy it. Each copy becomes a token.)

Ordruun Mentor

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Whenever you attack a player, target creature that's attacking that player gains first strike until end of turn.

Jacked Rabbit

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Whenever this creature attacks, create a number of 1/1 white Rabbit creature tokens equal to this creature's power.

Barbflare Gremlin

First strike, haste
Whenever a player taps a land for mana, if this creature is tapped, that player adds one mana of any type that land produced. Then that land deals 1 damage to that player.

Charismatic Conqueror

Vigilance
Whenever an artifact or creature an opponent controls enters untapped, they may tap that permanent. If they don't, you create a 1/1 white Vampire creature token with lifelink.

Guardian Scalelord

Backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following abilities until end of turn.)
Flying
Whenever this creature attacks, return target nonland permanent card with mana value X or less from your graveyard to the battlefield, where X is this creature's power.

Jenny, Generated Anomaly

Double strike
Whenever Jenny deals combat damage to a player, it explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.)

Death-Greeter's Champion

Dash {3}{R} (You may cast this spell for its dash cost. If you do, it gains haste, and it's returned from the battlefield to its owner's hand at the beginning of the next end step.)
Backup 1 (When this creature enters, put a +1/+1 counter on target creature. If that's another creature, it gains the following ability until end of turn.)
Double strike

Redoubled Stormsinger

First strike
Whenever this creature attacks, for each creature token you control that entered this turn, create a tapped and attacking token that's a copy of that token. At the beginning of the next end step, sacrifice those tokens.

Aradesh, the Founder

Enlist (As this creature attacks, you may tap a nonattacking creature you control without summoning sickness. When you do, add its power to this creature's until end of turn.)
Whenever a creature you control attacks, if it enlisted a creature this combat, the creature that attacked gains double strike until end of turn. If that creature's power is 4 or greater, draw a card.

Slicer, High-Speed Antagonist

Living metal (During your turn, this Vehicle is also a creature.)
First strike, haste
Whenever Slicer deals combat damage to a player, convert it at end of combat.

Slicer, Hired Muscle

More Than Meets the Eye {2}{R} (You may cast this card converted for {2}{R}.)
Double strike, haste
At the beginning of each opponent's upkeep, you may have that player gain control of Slicer until end of turn. If you do, untap Slicer, goad it, and it can't be sacrificed this turn. If you don't, convert it.

Slicer, Hired Muscle // Slicer, High-Speed Antagonist

Neyali, Suns' Vanguard

Attacking tokens you control have double strike.
Whenever one or more tokens you control attack a player, exile the top card of your library. During any turn you attacked with a token, you may play that card.

Ogre Battlecaster

First strike
Whenever this creature attacks, you may cast target instant or sorcery card from your graveyard by paying {R}{R} in addition to its other costs. If that spell would be put into a graveyard, exile it instead. When you cast that spell, this creature gets +X/+0 until end of turn, where X is that spell's mana value.

Ironwill Forger

Lieutenant — At the beginning of combat on your turn, if you control your commander, target nonlegendary creature you control gains myriad until end of turn. (Whenever it attacks, for each opponent other than defending player, you may create a token copy that's tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)