Artifacts you control have indestructible. (Effects that say "destroy" don't destroy them. Artifact creatures with indestructible can't be destroyed by damage.)

Indestructible

Darksteel Juggernaut's power and toughness are each equal to the number of artifacts you control.

Darksteel Juggernaut attacks each combat if able.

Imprint -- When Duplicant enters the battlefield, you may exile target nontoken creature.

As long as a card exiled with Duplicant is a creature card, Duplicant has the power, toughness, and creature types of the last creature card exiled with Duplicant. It's still a Shapeshifter.

Metalcraft -- Etched Champion has protection from all colors as long as you control three or more artifacts.

Artifact spells you cast cost {1} less to cast.

Trample

Whenever Geode Golem deals combat damage to a player, you may cast your commander from the command zone without paying its mana cost. (You still pay any additional costs.)

Hangarback Walker enters the battlefield with X +1/+1 counters on it.

When Hangarback Walker dies, create a 1/1 colorless Thopter artifact creature token with flying for each +1/+1 counter on Hangarback Walker.

{1}, {T}: Put a +1/+1 counter on Hangarback Walker.

+1: Reveal the top two cards of your library. An opponent chooses one of them. Put that card into your hand and exile the other with a silver counter on it.

-1: Put a card you own with a silver counter on it from exile into your hand.

-2: Create a 0/0 colorless Construct artifact creature token with "This creature gets +1/+1 for each artifact you control."

Whenever Karn, Silver Golem blocks or becomes blocked, it gets -4/+4 until end of turn.

{1}: Target noncreature artifact becomes an artifact creature with power and toughness each equal to its mana value until end of turn.

Activated abilities of artifacts your opponents control can't be activated.

+1: Until your next turn, up to one target noncreature artifact becomes an artifact creature with power and toughness each equal to its mana value.

-2: You may reveal an artifact card you own from outside the game or choose a face-up artifact card you own in exile. Put that card into your hand.

Nonartifact spells cost {1} more to cast.

Affinity for artifacts (This spell costs {1} less to cast for each artifact you control.)

Artifact creature spells you cast have affinity for artifacts. (They cost {1} less to cast for each artifact you control.)

When Myr Retriever dies, return another target artifact card from your graveyard to your hand.

You may look at the top card of your library any time.

You may cast artifact spells and colorless spells from the top of your library.

{T}, Pay 1 life: Exile the top card of your library.

Whenever Scrap Trawler or another artifact you control is put into a graveyard from the battlefield, return to your hand target artifact card in your graveyard with lesser mana value.

{T}: Add {C}{C}.

When Solemn Simulacrum enters the battlefield, you may search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

When Solemn Simulacrum dies, you may draw a card.

{T}: Put a +1/+1 counter on each artifact creature you control.

Reach, trample, protection from multicolored

Stonecoil Serpent enters the battlefield with X +1/+1 counters on it.

{T}: Add {C}{C}{C}.

Untap all artifacts you control during each other player's untap step.