msem-instigator

First mate — Each nonland card in your starting deck has “+1/+1 counter” or “harmonize” in its printed rules text. (If this card outside the game is your chosen first mate, you may swap it with a card in your opening hand.)
Once each turn, if one or more +1/+1 counters would be put on a permanent you control, you may put twice that many of those counters on it instead.
Once each turn, if you would trigger a harmony ability of a permanent you control, you may have that ability trigger twice instead.

When Lilyreed Triton enters, create a white Aura enchantment token named Triton's Gift attached to target creature. The token has enchant creature and “Enchanted creature gets +1/+0 and can't be blocked by creatures with power 3 or greater.”

Lifelink
Attain {4}{W} ({4}{W}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

Aura and Equipment spells you cast cost {1} less to cast.

Whenever Little Kibo attacks, you may pay {W}{W}. If you do, transform it.

When Little Pig enters, if you control a land named Far-Off Lands, put two +1/+1 counters on it.

Livia's name is Senaturian Legion in addition to its other names as long as it's on the battlefield.
At the beginning of your upkeep, conjure a card named Senaturian Legion into your hand, then discard a card. (It's a 1/1 Human Soldier for {W}{W} that gets +1/+1 for each other creature on the battlefield named Senaturian Legion.)
Other Soldiers you control have haste.

Trample
Whenever Living Archipelago enters or attacks, up to two target lands you control voyage. (If they aren't being targeted by another spell or ability, they phase out.)
Whenever a land you control phases in, you may create a tapped token that's a copy of that land.

Whenever you cast a noncreature spell, you may have target player mill two cards. Then if a player has twenty or fewer cards in their library, put a +1/+1 counter on Living Atrocity.

Flying, lifelink
Other Demons you control have flying and lifelink.
If you would create a creature token, you may instead pay 5 life and create a 5/5 black Demon creature token.

Whenever you attack with two or more Knights and/or Soldiers, you may have one of them seek valor. (Give it that Oath Aura. Fulfill it by it dealing combat damage to a player to create a 2/1 white Soldier token.)

When this creature enters, if you gained or lost life this turn, it seeks valor. (Give it that Oath Aura. Fulfill it by it dealing combat damage to a player to create a 2/1 white Soldier token.)

Whenever another creature you control enters, Loisch deals 1 damage to any target.
{4}{R}{G}: Loisch gets +X/+X and gains trample until end of turn, where X is the number of creatures you control.

Whenever Lone Freelancer becomes blocked, it deals damage equal to its power to defending player.

As long as you control no other Humans, Lone Survivor gets +2/+2 and has “Noncreature spells cost {1} more to cast.”

Menace
When Lone Zombie and at least two other creatures attack, transform Lone Zombie.

Menace
Lonely Devil can't attack or block alone.

Trample
Augmented — When Lonely Giant enters, if you've spent {W}{U}{B}{R}{G} to cast spells this turn, put two +1/+1 counters on it.

Flying, deathtouch

{2}{G}: Put a +1/+1 counter on Lonesome Ravager.
Ride {G} ({G}: Transform this and attach it to target creature you control without a Steed. Ride only as a sorcery.)

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)

Menace
Lonesome Trio can't attack or block unless at least three other creatures you control also attack or block.

Trample
Whenever you cycle Long-Term Method Actor or it attacks, proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)
Basic landcycling {1}{G} ({1}{G}, Discard this card: Search your library for a basic land card, reveal it, and put it into your hand, then shuffle.)

At the beginning of each opponent's upkeep, choose one —
• At the beginning of the next end step, if you haven't been dealt combat damage this turn, Lord Dalehorn the Iron-Handed deals 3 damage to that player.
• At the beginning of the next end step, if that player hasn't cast a creature spell this turn, Lord Dalehorn the Iron-Handed deals 3 damage to that player.

Flying
When Lord Rokai becomes the target of a spell, sacrifice it.
Whenever you cast an instant or sorcery spell, you may pay {2}{U}. If you do, return Lord Rokai from your graveyard to the battlefield.