Maelstrom Colossus

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Contagion Engine

When Contagion Engine enters, put a -1/-1 counter on each creature target player controls.
{4}, {T}: Proliferate twice. (Choose any number of permanents and/or players, then give each another counter of each kind already there. Then do it again.)

Champion of the Flame

Trample
Champion of the Flame gets +2/+2 for each Aura and Equipment attached to it.

Workshop Assistant

When Workshop Assistant dies, return another target artifact card from your graveyard to your hand.

Staunch Throneguard

Vigilance
When Staunch Throneguard enters, you become the monarch.

Stonefury

Stonefury deals damage to target creature equal to the number of lands you control.

Filigree Familiar

When Filigree Familiar enters, you gain 2 life.
When Filigree Familiar dies, draw a card.

Toggo, Goblin Weaponsmith

Landfall — Whenever a land you control enters, create a colorless Equipment artifact token named Rock with "Equipped creature has '{1}, {T}, Sacrifice Rock: This creature deals 2 damage to any target'" and equip {1}.
Partner (You can have two commanders if both have partner.)

Seer's Lantern

{T}: Add {C}.
{2}, {T}: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Haunted Cloak

Equipped creature has vigilance, trample, and haste.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Farhaven Elf

When Farhaven Elf enters, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Ferrovore

{R}, Sacrifice an artifact: Ferrovore gets +3/+0 until end of turn.

Fertilid

Fertilid enters with two +1/+1 counters on it.
{1}{G}, Remove a +1/+1 counter from Fertilid: Target player searches their library for a basic land card, puts it onto the battlefield tapped, then shuffles.

Wildheart Invoker

{8}: Target creature gets +5/+5 and gains trample until end of turn. (It can deal excess combat damage to the player or planeswalker it's attacking.)

Entourage of Trest

When Entourage of Trest enters, you become the monarch.
Entourage of Trest can block an additional creature each combat as long as you're the monarch.

Forest

Perilous Myr

When Perilous Myr dies, it deals 2 damage to any target.

Command Tower

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

Fire Diamond

Fire Diamond enters tapped.
{T}: Add {R}.

Foundry Inspector

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

Saberclaw Golem

{R}: Saberclaw Golem gains first strike until end of turn.

Horizon Spellbomb

{2}, {T}, Sacrifice Horizon Spellbomb: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.
When Horizon Spellbomb is put into a graveyard from the battlefield, you may pay {G}. If you do, draw a card.

Soul's Fire

Target creature you control deals damage equal to its power to any target.

Biowaste Blob

Oozes you control get +1/+1.
At the beginning of your upkeep, if you control a commander, create a token that's a copy of Biowaste Blob.

Armory of Iroas

Whenever equipped creature attacks, put a +1/+1 counter on it.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Natural Reclamation

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Destroy target artifact or enchantment.

Mountain

Furnace Celebration

Whenever you sacrifice another permanent, you may pay {2}. If you do, Furnace Celebration deals 2 damage to any target.

Ordeal of Nylea

Enchant creature
Whenever enchanted creature attacks, put a +1/+1 counter on it. Then if it has three or more +1/+1 counters on it, sacrifice this Aura.
When you sacrifice this Aura, search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Ich-Tekik, Salvage Splicer

When Ich-Tekik, Salvage Splicer enters, create a 3/3 colorless Phyrexian Golem artifact creature token.
Whenever an artifact is put into a graveyard from the battlefield, put a +1/+1 counter on Ich-Tekik and a +1/+1 counter on each Golem you control.
Partner (You can have two commanders if both have partner.)

Command Beacon

{T}: Add {C}.
{T}, Sacrifice Command Beacon: Put your commander into your hand from the command zone.

Lumengrid Gargoyle

Sisay's Ring

Howling Golem

Whenever Howling Golem attacks or blocks, each player draws a card.

Stingerfling Spider

Reach
When Stingerfling Spider enters, you may destroy target creature with flying.

Annoyed Altisaur

Reach, trample
Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Brazen Freebooter

When Brazen Freebooter enters, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Pilgrim's Eye

Flying
When Pilgrim's Eye enters, you may search your library for a basic land card, reveal it, put it into your hand, then shuffle.