Gargantuan Gorilla

At the beginning of your upkeep, you may sacrifice a Forest. If you sacrifice a snow Forest this way, this creature gains trample until end of turn. If you don't sacrifice a Forest, sacrifice this creature and it deals 7 damage to you.
{T}: This creature deals damage equal to its power to another target creature. That creature deals damage equal to its power to this creature.

Wrenn and Seven

+1: Reveal the top four cards of your library. Put all land cards revealed this way into your hand and the rest into your graveyard.
0: Put any number of land cards from your hand onto the battlefield tapped.
−3: Create a green Treefolk creature token with reach and "This token's power and toughness are each equal to the number of lands you control."
−8: Return all permanent cards from your graveyard to your hand. You get an emblem with "You have no maximum hand size."

Ride the Shoopuf

Landfall — Whenever a land you control enters, put a +1/+1 counter on target creature you control.
{5}{G}{G}: This enchantment becomes a 7/7 Beast creature in addition to its other types.

Reclamation Sage

When this creature enters, you may destroy target artifact or enchantment.

Elderscale Wurm

Trample
When this creature enters, if your life total is less than 7, your life total becomes 7.
As long as you have 7 or more life, damage that would reduce your life total to less than 7 reduces it to 7 instead.

Cloud, Ex-SOLDIER

Haste
When Cloud enters, attach up to one target Equipment you control to it.
Whenever Cloud attacks, draw a card for each equipped attacking creature you control. Then if Cloud has power 7 or greater, create two Treasure tokens.

Sephiroth, Fallen Hero

Jenova Cells — Whenever Sephiroth attacks, you may put a cell counter on target creature. Until end of turn, each modified creature you control has base power and toughness 7/5. (Equipment, Auras you control, and counters are modifications.)
The Reunion — {3}, Sacrifice a modified creature: Return this card from your graveyard to the battlefield tapped.

Tifa, Martial Artist

Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)
Whenever one or more creatures you control with power 7 or greater deal combat damage to a player, untap all creatures you control. If it's the first combat phase of your turn, there is an additional combat phase after this phase.

Avalanche of Sector 7

Menace
Avalanche of Sector 7's power is equal to the number of artifacts your opponents control.
Whenever an opponent activates an ability of an artifact they control, Avalanche of Sector 7 deals 1 damage to that player.

Saruli Gatekeepers

When this creature enters, if you control two or more Gates, you gain 7 life.

Seven Dwarves

This creature gets +1/+1 for each other creature named Seven Dwarves you control.
A deck can have up to seven cards named Seven Dwarves.

Promised Kannushi

Soulshift 7 (When this creature dies, you may return target Spirit card with mana value 7 or less from your graveyard to your hand.)

The Akroan War

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I — Gain control of target creature for as long as this Saga remains on the battlefield.
II — Until your next turn, creatures your opponents control attack each combat if able.
III — Each tapped creature deals damage to itself equal to its power.

Bugenhagen, Wise Elder

Reach
At the beginning of your upkeep, if you control a creature with power 7 or greater, draw a card.
{T}: Add one mana of any color.

Aerith, Last Ancient

Lifelink
Raise — At the beginning of your end step, if you gained life this turn, return target creature card from your graveyard to your hand. If you gained 7 or more life this turn, return that card to the battlefield instead.

Sire of Seven Deaths

First strike, vigilance
Menace, trample
Reach, lifelink
Ward—Pay 7 life.

Gigantomancer

{1}: Target creature you control has base power and toughness 7/7 until end of turn.