Have

Case of the Gateway Express

When this Case enters, choose target creature you don't control. Each creature you control deals 1 damage to that creature.
To solve — Three or more creatures attacked this turn. (If unsolved, solve at the beginning of your end step.)
Solved — Creatures you control get +1/+0.

Don't Have

Web of Life and Destiny

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
At the beginning of combat on your turn, look at the top five cards of your library. You may put a creature card from among them onto the battlefield. Put the rest on the bottom of your library in a random order.

Getting

Overlord of the Mistmoors

Impending 4—{2}{W}{W} (If you cast this spell for its impending cost, it enters with four time counters and isn't a creature until the last is removed. At the beginning of your end step, remove a time counter from it.)
Whenever this permanent enters or attacks, create two 2/1 white Insect creature tokens with flying.

Sandstorm Salvager

When this creature enters, create a 3/3 colorless Golem artifact creature token.
{2}, {T}: Put a +1/+1 counter on each creature token you control. They gain trample until end of turn.

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

Porcelain Gallery

Creatures you control have base power and toughness each equal to the number of creatures you control.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Dollmaker's Shop

Whenever one or more non-Toy creatures you control attack a player, create a 1/1 white Toy artifact creature token.
(You may cast either half. That door unlocks on the battlefield. As a sorcery, you may pay the mana cost of a locked door to unlock it.)

Dollmaker's Shop // Porcelain Gallery

Forest

Optimistic Scavenger

Eerie — Whenever an enchantment you control enters and whenever you fully unlock a Room, put a +1/+1 counter on target creature.

Collector's Cage

Hideaway 5 (When this artifact enters, look at the top five cards of your library, exile one face down, then put the rest on the bottom in a random order.)
{1}, {T}: Put a +1/+1 counter on target creature you control. Then if you control three or more creatures with different powers, you may play the exiled card without paying its mana cost.

Llanowar Elves

Multiversal Passage

As this land enters, choose a basic land type. Then you may pay 2 life. If you don't, it enters tapped.
This land is the chosen type.

Hushwood Verge

{T}: Add {G}.
{T}: Add {W}. Activate only if you control a Forest or a Plains.

Plains

Pawpatch Recruit

Offspring {2} (You may pay an additional {2} as you cast this spell. If you do, when this creature enters, create a 1/1 token copy of it.)
Trample
Whenever a creature you control becomes the target of a spell or ability an opponent controls, put a +1/+1 counter on target creature you control other than that creature.

Valgavoth's Lair

Hexproof
This land enters tapped. As it enters, choose a color.
{T}: Add one mana of the chosen color.

Brushland

{T}: Add {C}.
{T}: Add {G} or {W}. This land deals 1 damage to you.

Restless Prairie

This land enters tapped.
{T}: Add {G} or {W}.
{2}{G}{W}: This land becomes a 3/3 green and white Llama creature until end of turn. It's still a land.
Whenever this land attacks, other creatures you control get +1/+1 until end of turn.

Starting Town

This land enters tapped unless it's your first, second, or third turn of the game.
{T}: Add {C}.
{T}, Pay 1 life: Add one mana of any color.

Elspeth, Storm Slayer

If one or more tokens would be created under your control, twice that many of those tokens are created instead.
+1: Create a 1/1 white Soldier creature token.
0: Put a +1/+1 counter on each creature you control. Those creatures gain flying until your next turn.
−3: Destroy target creature an opponent controls with mana value 3 or greater.

Dalkovan Packbeasts

Vigilance
Mobilize 3 (Whenever this creature attacks, create three tapped and attacking 1/1 red Warrior creature tokens. Sacrifice them at the beginning of the next end step.)

Elvish Archivist

Whenever one or more artifacts you control enter, put two +1/+1 counters on this creature. This ability triggers only once each turn.
Whenever one or more enchantments you control enter, draw a card. This ability triggers only once each turn.