Goldberry, River-Daughter

{T}: Move a counter of each kind not on Goldberry from another target permanent you control onto Goldberry.
{U}, {T}: Move one or more counters from Goldberry onto another target permanent you control. If you do, draw a card.

Lotho, Corrupt Shirriff

Whenever a player casts their second spell each turn, you lose 1 life and create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Kudo, King Among Bears

Other creatures have base power and toughness 2/2 and are Bears in addition to their other types.

Arna Kennerüd, Skycaptain

Flying, lifelink
Ward—Discard a card.
Whenever a modified creature you control attacks, double the number of each kind of counter on it. Then for each nontoken permanent attached to it, create a token that's a copy of that permanent attached to that creature.

Tinybones, Bauble Burglar

Whenever an opponent discards a card, exile it from their graveyard with a stash counter on it.
During your turn, you may play cards you don't own with stash counters on them from exile, and mana of any type can be spent to cast those spells.
{3}{B}, {T}: Each opponent discards a card. Activate only as a sorcery.

Brigid, Hero of Kinsbaile

First strike
{T}: Brigid deals 2 damage to each attacking or blocking creature target player controls.

Kira, Great Glass-Spinner

Flying
Creatures you control have "Whenever this creature becomes the target of a spell or ability for the first time each turn, counter that spell or ability."

Brigone, Soldier of Meletis

Vigilance
Heroic — Whenever you cast a spell that targets Brigone, put a +1/+1 counter on Brigone.
{T}, Remove a +1/+1 counter from Brigone: Draw a card.

Vnwxt, Verbose Host

Start your engines! (If you have no speed, it starts at 1. It increases once on each of your turns when an opponent loses life. Max speed is 4.)
You have no maximum hand size.
Max speed — If you would draw a card, draw two cards instead.

Linden, the Steadfast Queen

Vigilance (Attacking doesn't cause this creature to tap.)
Whenever a white creature you control attacks, you gain 1 life.

Taigam, Master Opportunist

Flurry — Whenever you cast your second spell each turn, copy it, then exile the spell you cast with four time counters on it. If it doesn't have suspend, it gains suspend. (At the beginning of its owner's upkeep, they remove a time counter. When the last is removed, they may play it without paying its mana cost. If it's a creature, it has haste.)

Bane, Lord of Darkness

As long as your life total is less than or equal to half your starting life total, Bane has indestructible.
Whenever another nontoken creature you control dies, target opponent may have you draw a card. If they don't, you may put a creature card with equal or lesser toughness from your hand onto the battlefield.

Taigam, Ojutai Master

Instant, sorcery, and Dragon spells you control can't be countered.
Whenever you cast an instant or sorcery spell from your hand, if Taigam attacked this turn, that spell gains rebound. (Exile the spell as it resolves. At the beginning of your next upkeep, you may cast that card from exile without paying its mana cost.)

The Celestial Toymaker

Whenever The Celestial Toymaker attacks, look at the top three cards of your library. Exile any number of them in a face-down pile and the rest in a face-up pile. Defending player chooses one of those piles. Put that pile into your hand.
At the beginning of each end step, each opponent loses 2 life for each spell or ability that caused one or more players to guess or to group cards or permanents into a pile this turn.

Vega, the Watcher

Flying
Whenever you cast a spell from anywhere other than your hand, draw a card.

Riku of Many Paths

Whenever you cast a modal spell, choose up to X, where X is the number of times you chose a mode for that spell —
• Exile the top card of your library. Until the end of your next turn, you may play it.
• Put a +1/+1 counter on Riku. It gains trample until end of turn.
• Create a 1/1 blue Bird creature token with flying.

Marvin, Murderous Mimic

Marvin has all activated abilities of creatures you control that don't have the same name as this creature.

Lurrus of the Dream-Den

Companion — Each permanent card in your starting deck has mana value 2 or less. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
Lifelink
Once during each of your turns, you may cast a permanent spell with mana value 2 or less from your graveyard.

Colonel Autumn

Lifelink
Exploit (When this creature enters, you may sacrifice a creature.)
Other legendary creatures you control have exploit.
Whenever a creature you control exploits a creature, put a +1/+1 counter on each creature you control.

Odric, Lunarch Marshal

At the beginning of each combat, creatures you control gain first strike until end of turn if a creature you control has first strike. The same is true for flying, deathtouch, double strike, haste, hexproof, indestructible, lifelink, menace, reach, skulk, trample, and vigilance.

Melek, Reforged Researcher

Melek's power and toughness are each equal to twice the number of instant and sorcery cards in your graveyard.
The first instant or sorcery spell you cast each turn costs {3} less to cast.

Kiora, the Rising Tide

When Kiora enters, draw two cards, then discard two cards.
Threshold — Whenever Kiora attacks, if there are seven or more cards in your graveyard, you may create Scion of the Deep, a legendary 8/8 blue Octopus creature token.

Agatha of the Vile Cauldron

Activated abilities of creatures you control cost {X} less to activate, where X is Agatha's power. This effect can't reduce the mana in that cost to less than one mana.
{4}{R}{G}: Other creatures you control get +1/+1 and gain trample and haste until end of turn.

Thalia, Heretic Cathar

First strike
Creatures and nonbasic lands your opponents control enter tapped.

Lae'zel, Vlaakith's Champion

If you would put one or more counters on a creature or planeswalker you control or on yourself, put that many plus one of each of those kinds of counters on that permanent or player instead.
Choose a Background (You can have a Background as a second commander.)