Arthur, Marigold Knight

Haste
Whenever Arthur and at least one other creature attack, look at the top six cards of your library. You may put a creature card from among them onto the battlefield tapped and attacking. Put the rest on the bottom of your library in a random order. Return that creature to its owner's hand at end of combat.

Berserkers' Onslaught

Attacking creatures you control have double strike.

Windbrisk Raptor

Flying
Attacking creatures you control have lifelink.

Tori D'Avenant, Fury Rider

Vigilance, trample
Whenever Tori D'Avenant attacks, all other attacking creatures you control get +1/+1 until end of turn. Other red attacking creatures you control gain trample until end of turn. Untap each other white attacking creature you control.

Anger

Haste
As long as this card is in your graveyard and you control a Mountain, creatures you control have haste.

Valor

First strike
As long as this card is in your graveyard and you control a Plains, creatures you control have first strike.

Professional Face-Breaker

Menace
Whenever one or more creatures you control deal combat damage to a player, create a Treasure token.
Sacrifice a Treasure: Exile the top card of your library. You may play that card this turn.

Blade Historian

Wonder

Flying
As long as this card is in your graveyard and you control an Island, creatures you control have flying.

Flowering of the White Tree

Legendary creatures you control get +2/+1 and have ward {1}.
Nonlegendary creatures you control get +1/+1.

Iroas, God of Victory

Indestructible
As long as your devotion to red and white is less than seven, Iroas isn't a creature.
Creatures you control have menace.
Prevent all damage that would be dealt to attacking creatures you control.

Dolmen Gate

Prevent all combat damage that would be dealt to attacking creatures you control.

Stensia Masquerade

Attacking creatures you control have first strike.
Whenever a Vampire you control deals combat damage to a player, put a +1/+1 counter on it.
Madness {2}{R} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)