Enchant opponent
Whenever you attack enchanted player, that player loses 2 life. You draw a card and gain 2 life.
Whenever a player attacks you, you may attach this Aura to that player.

: Look at target player's hand.

As an additional cost to cast this spell, you may choose a creature type and behold two creatures of that type.
Search your library for a creature card with mana value X or less, reveal it, put it into your hand, then shuffle. If this spell's additional cost was paid and the revealed card is the chosen type, put that card onto the battlefield instead of putting it into your hand.

Trample
When this creature enters, create two Food tokens. (They're artifacts with ", , Sacrifice this token: You gain 3 life.")
Whenever this creature attacks, you may sacrifice a Food. If you do, mill three cards. You may put a permanent card from among them into your hand.

Whenever you draw your second card each turn, each opponent loses 2 life and you gain 2 life.
When this creature dies, return another target creature card with mana value 3 or less from your graveyard to the battlefield.

First strike, haste

Double strike, protection from black and from green

Choose a creature type. Return up to two creature cards of that type from your graveyard to the battlefield. If this spell was foretold, return all creature cards of that type from your graveyard to the battlefield instead.
Foretell (During your turn, you may pay and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Emerge (You may cast this spell by sacrificing a creature and paying the emerge cost reduced by that creature's mana value.)
When you cast this spell, you may exile your hand. If you do, draw three cards.
Flying
Each creature spell you cast has emerge. The emerge cost is equal to its mana cost.

Whenever Alex Wilder or another creature you control enters, if you cast it from anywhere other than your hand, it gets +2/+0 and gains haste until end of turn.
Escape—, Exile three other cards from your graveyard. (You may cast this card from your graveyard for its escape cost.)

During your turn, spells you cast cost less to cast for each creature you control with power 4 or greater.

: You may exile an instant or sorcery card from your hand and put three refine counters on it. It gains "At the beginning of your upkeep, if this card is exiled, remove a refine counter from it" and "When the last refine counter is removed from this card, if it's exiled, you may cast it. It costs less to cast this way."

: Add .
: Add or . Activate only if you control a Swamp.

Flying
Venom Blast — Artifacts and creatures your opponents control enter tapped.

: Add .

, , Sacrifice another artifact: Search your library for an artifact card with mana value equal to 1 plus the sacrificed artifact's mana value, put that card onto the battlefield, then shuffle. Activate only as a sorcery.

: Add .
, , Sacrifice a creature: Put a soul counter on this land. Then if there are three or more soul counters on it, remove those counters, transform it, then untap it. Activate only as a sorcery.

Equipped creature gets +3/+0 and has trample and lifelink.
Equip

First strike
Creatures and nonbasic lands your opponents control enter tapped.

Changeling (This card is every creature type.)
When this creature enters, create a tapped Mutavault token. (It's a land with ": Add " and ": This token becomes a 2/2 creature with all creature types until end of turn. It's still a land.")