Strength of Will

Until end of turn, target creature you control gains indestructible and "Whenever this creature is dealt damage, put that many +1/+1 counters on it."

Amazing Spider-Man

Vigilance, reach
Each legendary spell you cast that's one or more colors has web-slinging {G}{W}{U}. (You may cast a spell for its web-slinging cost if you also return a tapped creature you control to its owner's hand.)

Peter Parker

When Peter Parker enters, create a 2/1 green Spider creature token with reach.
{1}{G}{W}{U}: Transform Peter Parker. Activate only as a sorcery.

Peter Parker // Amazing Spider-Man

Getting

Vibrant Cityscape

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

City Pigeon

Flying
When this creature leaves the battlefield, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")

Peter Parker's Camera

This artifact enters with three film counters on it.
{2}, {T}, Remove a film counter from this artifact: Copy target activated or triggered ability you control. You may choose new targets for the copy.

Spider-Man 2099, Miguel O'Hara

When Spider-Man 2099 enters, return up to one target creature to its owner's hand.
Whenever one or more creatures you control deal combat damage to a player, draw a card.

Morlun, Devourer of Spiders

Lifelink
Morlun enters with X +1/+1 counters on him.
When Morlun enters, he deals X damage to target opponent.

Wraith, Vicious Vigilante

Double strike
Fear Gas — Wraith can't be blocked.

Sensational Spider-Man

Whenever Sensational Spider-Man attacks, tap target creature defending player controls and put a stun counter on it. Then you may remove up to three stun counters from among all permanents. Draw cards equal to the number of stun counters removed this way.

Lyla, Holographic Assistant

Whenever you draw a card, put a +1/+1 counter on target creature.

Spider-Rex, Daring Dino

Reach, trample
Ward {2} (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {2}.)

The Spot's Portal

Put target creature on the bottom of its owner's library. You lose 2 life unless you control a Villain.

MJ, Rising Star

Vigilance (Attacking doesn't cause this creature to tap.)
Whenever you gain life, put a +1/+1 counter on MJ.

Aunt May

Whenever another creature you control enters, you gain 1 life. If it's a Spider, put a +1/+1 counter on it.

Cheering Crowd

At the beginning of each player's first main phase, that player may put a +1/+1 counter on this creature. If they do, they add {C} for each counter on it.

Stegron the Dinosaur Man

Menace (This creature can't be blocked except by two or more creatures.)
Dinosaur Formula — {1}{R}, Discard this card: Until end of turn, target creature you control gets +3/+1 and becomes a Dinosaur in addition to its other types.

The Soul Stone

Indestructible
{T}: Add {B}.
{6}{B}, {T}, Exile a creature you control: Harness The Soul Stone. (Once harnessed, its ∞ ability is active.)
∞ — At the beginning of your upkeep, return target creature card from your graveyard to the battlefield.

Spider-Man, Miles Morales

Vigilance, trample (Attacking doesn't cause this creature to tap. He can deal excess combat damage to the player he's attacking.)
Whenever Spider-Man enters or attacks, put a +1/+1 counter on each other creature you control. Those creatures gain trample until end of turn.

Agent Venom

Flash
Menace
Whenever another nontoken creature you control dies, you draw a card and lose 1 life.

Spectacular Spider-Man

Flash
{1}: Spectacular Spider-Man gains flying until end of turn.
{1}, Sacrifice Spectacular Spider-Man: Creatures you control gain hexproof and indestructible until end of turn.

Silk, Web Weaver

Web-slinging {1}{G}{W} (You may cast this spell for {1}{G}{W} if you also return a tapped creature you control to its owner's hand.)
Whenever you cast a creature spell, create a 1/1 green and white Human Citizen creature token.
{3}{G}{W}: Creatures you control get +2/+2 and gain vigilance until end of turn.

Sandman, Shifting Scoundrel

Sandman's power and toughness are each equal to the number of lands you control.
Sandman can't be blocked by creatures with power 2 or less.
{3}{G}{G}: Return this card and target land card from your graveyard to the battlefield tapped.

Grow Extra Arms

This spell costs {1} less to cast if it targets a Spider.
Target creature gets +4/+4 until end of turn.

Hobgoblin, Mantled Marauder

Flying, haste
Whenever you discard a card, Hobgoblin gets +2/+0 until end of turn.

J. Jonah Jameson

When J. Jonah Jameson enters, suspect up to one target creature. (A suspected creature has menace and can't block.)
Whenever a creature you control with menace attacks, create a Treasure token.

Spider-Ham, Peter Porker

When Spider-Ham enters, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")
Animal May-Ham — Other Spiders, Boars, Bats, Bears, Birds, Cats, Dogs, Frogs, Jackals, Lizards, Mice, Otters, Rabbits, Raccoons, Rats, Squirrels, Turtles, and Wolves you control get +1/+1.

Maximum Carnage

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Until your next turn, each creature attacks each combat if able and attacks a player other than you if able.
II — Add {R}{R}{R}.
III — This Saga deals 5 damage to each opponent.

Plains

Pumpkin Bombs

{T}, Discard two cards: Draw three cards, then put a fuse counter on this artifact. It deals damage equal to the number of fuse counters on it to target opponent. They gain control of this artifact.

Urban Retreat

This land enters tapped.
{T}: Add {G}, {W}, or {U}.
{2}, Return a tapped creature you control to its owner's hand: Put this card from your hand onto the battlefield. Activate only as a sorcery.

Impostor Syndrome

Whenever a nontoken creature you control deals combat damage to a player, create a token that's a copy of it, except it isn't legendary.

Venom, Lethal Protector

Menace, trample, haste
Whenever Venom attacks, you may sacrifice another creature. If you do, draw X cards, then you may put a permanent card with mana value X or less from your hand onto the battlefield, where X is the sacrificed creature's mana value.

Eddie Brock

When Eddie Brock enters, return target creature card with mana value 1 or less from your graveyard to the battlefield.
{3}{B}{R}{G}: Transform Eddie Brock. Activate only as a sorcery.