Legendary Creature — Elemental Hero

Flying, hexproof, prowess
Whenever you cast a noncreature spell, put a +1/+1 counter on each other creature you control.

Photon, Living Light

Marvel Super Heroes

Legendary Creature — Human Hero

Flying, prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
{2}{R}{W}{W}: Transform Monica Rambeau. Activate only as a sorcery.

Monica Rambeau

Legendary Creature — Human Warrior Hero

Flash
Double strike
Prevent all damage that would be dealt to Black Panther.
Whenever Black Panther deals combat damage to a player, draw a card.

Black Panther, Hope Enduring

Legendary Creature — Human Noble Hero

Flash
Whenever a player draws their second card each turn, you draw a card.
{4}{W}{U}: Transform King T'Challa. Activate only as a sorcery.

King T'Challa

Legendary Artifact Creature — Human Hero

Flying, haste
At the beginning of combat on your turn, you may put an artifact card from your hand onto the battlefield. If it's an Equipment, attach it to The Invincible Iron Man.

The Invincible Iron Man

Legendary Creature — Human Artificer Hero

{1}, {T}: Look at the top four cards of your library. You may reveal an artifact card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
{4}{U}{R}: Transform Tony Stark. Activate only as a sorcery.