Trample
When this creature enters, each opponent loses 3 life and you gain 3 life.

Whenever you sacrifice this artifact or another artifact, you may pay . If you do, at the beginning of the next end step, create a token that's a copy of that artifact.
, Sacrifice this artifact: Draw a card.

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: Remove target blocking creature from combat. Creatures it was blocking that hadn't become blocked by another creature this combat become unblocked, then it blocks an attacking creature of your choice. Activate only during the declare blockers step.

This spell costs less to cast, where X is the total power of creatures you control.
Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)

, , Sacrifice this artifact: Search target player's library for three cards and exile them. Then that player shuffles.

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Enchant player
Enchanted player can't gain life.
Whenever enchanted player is dealt damage, they lose half their life, rounded up.

Artifact spells you cast cost less to cast.

, Remove a +1/+1 counter or a charge counter from a permanent you control: This enchantment deals 2 damage to any target.

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When you cast this spell, gain control of target creature until end of turn. Untap it. It gains menace and haste until end of turn.
The Beast enters tapped with six stun counters on it. (If it would become untapped, remove a stun counter from it instead.)
Whenever a creature deals combat damage to its owner, untap The Beast and draw a card.

Dynastic Command Node — As long as you control your commander, activated abilities of cards in your graveyard cost less to activate. This effect can't reduce the mana in that ability's activation cost to less than one mana.
Translocation Protocols — , : Mill three cards.

Ravenous (This creature enters with X +1/+1 counters on it. If X is 5 or more, draw a card when it enters.)
Endless Swarm — Whenever a land you control enters, you may pay . If you do, return this card from your graveyard to your hand.

Prevent all combat damage that would be dealt this turn.

Domain — All creatures get -1/-1 until end of turn for each basic land type among lands you control.

Counter target spell unless its controller pays .

Flying
Whenever another nontoken creature you control dies, you may exile it. If you do, create a token that's a copy of that creature, except it's 1/1 and it's a Nightmare in addition to its other types.

The first spell you cast from anywhere other than your hand each turn has demonstrate. (When you cast that spell, you may copy it. If you do, choose an opponent to also copy it. A copy of a permanent spell becomes a token.)
Whenever you copy a spell, put a +1/+1 counter on The Twelfth Doctor.

This creature can't block creatures with power 2 or greater.