Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for .)
Search your library for an artifact card with mana value X or less, put it onto the battlefield, then shuffle.

: Untap this artifact.
, : Create a 1/1 colorless Servo artifact creature token.
, , Sacrifice a Servo: Create a 1/1 colorless Thopter artifact creature token with flying.
, Sacrifice a Thopter: Create a 4/4 colorless Construct artifact creature token.

(: Add .)

Flash
This spell costs less to cast for each attacking creature you control.
When Embercleave enters, attach it to target creature you control.
Equipped creature gets +1/+1 and has double strike and trample.
Equip

When Exdeath enters, you gain 3 life.
At the beginning of your end step, if there are six or more permanent cards in your graveyard, transform Exdeath.

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

, Mill a card: Add . (Activate only as an instant. To mill a card, put the top card of your library into your graveyard.)

: Add .
: Add or . This artifact deals 1 damage to you.

, Sacrifice a permanent: You gain 1 life.

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

You may have this creature enter as a copy of any creature on the battlefield.

When Muxus enters, reveal the top six cards of your library. Put all Goblin creature cards with mana value 5 or less from among them onto the battlefield and the rest on the bottom of your library in a random order.
Whenever Muxus attacks, it gets +1/+1 until end of turn for each other Goblin you control.

: Untap this artifact.
, : You gain 1 life.
, : Untap target creature.
, : Tap target creature.
, : Draw a card.

Level up (: Put a level counter on this. Level up only as a sorcery.)
LEVEL 1-4
1/2
: Add .
LEVEL 5+
1/4
Elves you control have ": Add ."

+1: Scry 1, then draw a card.
−2: Return target creature to its owner's hand.
−8: You get an emblem with "Whenever an opponent casts their first spell each turn, counter that spell."

Cumulative upkeep (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Whenever an opponent casts a noncreature spell, you may draw a card unless that player pays .

Whenever you cast a spell during an opponent's turn, you get an experience counter.
Whenever Katara attacks, you may draw a card for each experience counter you have. If you do, discard a card.

As an additional cost to cast this spell, exile six cards from your graveyard.
Flying
At the beginning of each opponent's upkeep, manifest dread. (Look at the top two cards of your library. Put one onto the battlefield face down as a 2/2 creature and the other into your graveyard. Turn it face up any time for its mana cost if it's a creature card.)

Reach, vigilance
If you would draw a card except the first one you draw in each of your draw steps, draw two cards instead.
If one or more tokens would be created under your control, twice that many of those tokens are created instead.

Flying
You have no maximum hand size.
Whenever a source you control deals noncombat damage to an opponent, you draw that many cards.