Excalibur, Sword of Eden

This spell costs {X} less to cast, where X is the total mana value of historic permanents you control. (Artifacts, legendaries, and Sagas are historic.)
Equipped creature gets +10/+0 and has vigilance.
Equip legendary creature {2}

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Go for the Throat

Abstergo Entertainment

{T}: Add {C}.
{1}, {T}: Add one mana of any color.
{3}, {T}, Exile Abstergo Entertainment: Return up to one target historic card from your graveyard to your hand, then exile all graveyards. (Artifacts, legendaries, and Sagas are historic.)

Lady Octopus, Inspired Inventor

Whenever you draw your first or second card each turn, put an ingenuity counter on Lady Octopus.
{T}: You may cast an artifact spell from your hand with mana value less than or equal to the number of ingenuity counters on Lady Octopus without paying its mana cost.

Flight

Enchant creature
Enchanted creature has flying.

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Tetsuo, Imperial Champion

Whenever Tetsuo attacks, if it's equipped, choose one —
• Tetsuo deals damage equal to the greatest mana value among Equipment attached to it to any target.
• You may cast an instant or sorcery spell from your hand with mana value less than or equal to the greatest mana value among Equipment attached to Tetsuo without paying its mana cost.

Darksteel Forge

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

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Ruby Medallion

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

Whispersilk Cloak

Equipped creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)
Equip {2}

Sapphire Medallion

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

Rogue's Passage

{T}: Add {C}.
{4}, {T}: Target creature can't be blocked this turn.

Mountain

Blasphemous Act

This spell costs {1} less to cast for each creature on the battlefield.
Blasphemous Act deals 13 damage to each creature.

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Anger

Haste
As long as this card is in your graveyard and you control a Mountain, creatures you control have haste.

Terramorphic Expanse

Jet Medallion

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

Tetsuo Umezawa

Tetsuo Umezawa can't be the target of Aura spells.
{U}{B}{B}{R}, {T}: Destroy target tapped or blocking creature.

Terror

Destroy target nonartifact, nonblack creature. It can't be regenerated.

Swamp

Wonder

Flying
As long as this card is in your graveyard and you control an Island, creatures you control have flying.

Komainu Battle Armor

Menace
Equipped creature gets +2/+2 and has menace.
Whenever this creature or equipped creature deals combat damage to a player, goad each creature that player controls.
Reconfigure {4} ({4}: Attach to target creature you control; or unattach from a creature. Reconfigure only as a sorcery. While attached, this isn't a creature.)

Sol Ring

Island

Access Tunnel

{T}: Add {C}.
{3}, {T}: Target creature with power 3 or less can't be blocked this turn.

Counterspell

Colossus Hammer

Equipped creature gets +10/+10 and loses flying.
Equip {8} ({8}: Attach to target creature you control. Equip only as a sorcery.)

Mirri the Cursed

Flying, first strike, haste
Whenever Mirri deals combat damage to a creature, put a +1/+1 counter on Mirri.

Mithril Coat

Flash
Indestructible
When Mithril Coat enters, attach it to target legendary creature you control.
Equipped creature has indestructible.
Equip {3}