Nelly Borca, Impulsive Accuser

Vigilance
Whenever Nelly Borca, Impulsive Accuser attacks, suspect target creature. Then goad all suspected creatures. (A suspected creature has menace and can't block.)
Whenever one or more creatures an opponent controls deal combat damage to one or more of your opponents, you and the controller of those creatures each draw a card.

Hamlet Captain

Whenever Hamlet Captain attacks or blocks, other Humans you control get +1/+1 until end of turn.

Karona, False God

Haste
At the beginning of each player's upkeep, that player untaps Karona, False God and gains control of it.
Whenever Karona attacks, creatures of the creature type of your choice get +3/+3 until end of turn.

Mardu Shadowspear

Whenever Mardu Shadowspear attacks, each opponent loses 1 life.
Dash {1}{B} (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.)

Mardu Strike Leader

Whenever Mardu Strike Leader attacks, create a 2/1 black Warrior creature token.
Dash {3}{B} (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.)

Edric, Spymaster of Trest

Whenever a creature deals combat damage to one of your opponents, its controller may draw a card.

Pianna, Nomad Captain

Whenever Pianna, Nomad Captain attacks, attacking creatures get +1/+1 until end of turn.

Immard, the Stormcleaver

Whenever Immard, the Stormcleaver enters or attacks, put a charge counter on it or remove one from it. When you remove a counter this way, choose one —
• Immard deals 4 damage to any target.
• Immard gains lifelink and indestructible until end of turn.

Stampede Surfer

Haste
Whenever Stampede Surfer attacks, for each opponent, you create a 2/2 green Boar creature token that's tapped and attacking that opponent.

Jolene, the Plunder Queen

Whenever a player attacks one or more of your opponents, that attacking player creates a Treasure token.
If you would create one or more Treasure tokens, instead create those tokens plus an additional Treasure token.
Sacrifice five Treasures: Put five +1/+1 counters on Jolene.

Hanweir Garrison

Whenever Hanweir Garrison attacks, create two 1/1 red Human creature tokens that are tapped and attacking.
(Melds with Hanweir Battlements.)