Panharmonicon

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

Determined Iteration

At the beginning of combat on your turn, populate. The token created this way gains haste. Sacrifice it at the beginning of the next end step. (To populate, create a token that's a copy of a creature token you control.)

Mirrorworks

Whenever another nontoken artifact you control enters, you may pay {2}. If you do, create a token that's a copy of that artifact.

Illusionist's Bracers

Whenever an ability of equipped creature is activated, if it isn't a mana ability, copy that ability. You may choose new targets for the copy.
Equip {3}

Cogwork Assembler

{7}: Create a token that's a copy of target artifact. That token gains haste. Exile it at the beginning of the next end step.

Lithoform Engine

{2}, {T}: Copy target activated or triggered ability you control. You may choose new targets for the copy.
{3}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy.
{4}, {T}: Copy target permanent spell you control. (The copy becomes a token.)

The Peregrine Dynamo

Haste
{1}, {T}: Copy target activated or triggered ability you control from another legendary source that's not a commander. You may choose new targets for the copy. (Mana abilities can't be targeted.)

Abstruse Archaic

Vigilance
{1}, {T}: Copy target activated or triggered ability you control from a colorless source. You may choose new targets for the copy. (Mana abilities can't be targeted.)

Mirage Mirror

{2}: Mirage Mirror becomes a copy of target artifact, creature, enchantment, or land until end of turn.

Academy Manufactor

If you would create a Clue, Food, or Treasure token, instead create one of each.

Street Urchin

Commander creatures you own have "{1}, Sacrifice another creature or an artifact: This creature deals 1 damage to any target."

Twinning Staff

If you would copy a spell one or more times, instead copy it that many times plus an additional time. You may choose new targets for the additional copy.
{7}, {T}: Copy target instant or sorcery spell you control. You may choose new targets for the copy.

Selesnya Eulogist

{2}{G}: Exile target creature card from a graveyard, then populate. (Create a token that's a copy of a creature token you control.)

Feldon of the Third Path

{2}{R}, {T}: Create a token that's a copy of target creature card in your graveyard, except it's an artifact in addition to its other types. It gains haste. Sacrifice it at the beginning of the next end step.

Second Harvest

For each token you control, create a token that's a copy of that permanent.

Esika's Chariot

When Esika's Chariot enters, create two 2/2 green Cat creature tokens.
Whenever Esika's Chariot attacks, create a token that's a copy of target token you control.
Crew 4

Dutiful Replicator

When Dutiful Replicator enters, you may pay {1}. When you do, create a token that's a copy of target token you control not named Dutiful Replicator.

Dino DNA

Imprint — {1}, {T}: Exile target creature card from a graveyard. Activate only as a sorcery.
{6}: Create a token that's a copy of target creature card exiled with Dino DNA, except it's a 6/6 green Dinosaur creature with trample. Activate only as a sorcery.

Sculpting Steel

You may have Sculpting Steel enter as a copy of any artifact on the battlefield.

Strionic Resonator

{2}, {T}: Copy target triggered ability you control. You may choose new targets for the copy. (A triggered ability uses the words "when," "whenever," or "at.")

Jaheira, Friend of the Forest

Tokens you control have "{T}: Add {G}."
Choose a Background (You can have a Background as a second commander.)

City of Death

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after VI.)
I — Create a Treasure token.
II, III, IV, V, VI — Create a token that's a copy of target non-Saga token you control.

Full Flowering

Populate X times. (To populate, create a token that's a copy of a creature token you control. Do this X times.)