Start your engines!
You have no maximum hand size.
Max speed — If you would draw a card, draw two cards instead.

Domain — When this creature enters, look at the top X cards of your library, where X is the number of basic land types among lands you control. You may put one of those cards on top of your library. Put the rest on the bottom of your library in a random order.

: Add . Spend this mana only to cast an instant or sorcery spell.

Flash
Other Merfolk you control get +1/+1.
Sacrifice a Merfolk: Counter target noncreature spell unless its controller pays .

, : Target player discards a card. Activate only as a sorcery.

, : Target creature phases out.

First strike
This creature can't attack unless defending player controls an Island.
When you control no Islands, sacrifice this creature.
: This creature gains flying until end of turn.

, : Counter target spell unless its controller pays .

When this creature enters, draw a card, then discard a card.

Kicker and/or
This creature enters with two +1/+1 counters on it for each time it was kicked.
When this creature enters, gain control of target creature with power less than this creature's power for as long as you control this creature.

: Target instant or sorcery spell becomes the color of your choice.

Kicker
This creature can't attack unless defending player controls an Island.
If this creature was kicked, it enters with four +1/+1 counters on it.

Defender
Tap an untapped Merfolk you control: This creature can attack this turn as though it didn't have defender.
Tap an untapped Merfolk you control: This creature gets +2/+1 until end of turn.
When this creature dies, destroy all Merfolk tapped this turn to pay for its abilities.

, : Put this creature and target creature on top of their owners' libraries, then those players shuffle their libraries.

Morph
When this creature is turned face up, counter target spell.

Flash
When this creature enters, counter target activated ability. (Mana abilities can't be targeted.)
Whenever you cast a spell, you may return this creature to its owner's hand.

, Sacrifice a Wizard: Counter target spell.
Morph

When this creature enters, you may return target creature to its owner's hand.

Flying, hexproof from activated and triggered abilities
When this creature enters, exchange control of this creature and target creature an opponent controls. If you do, you get , then sacrifice that creature unless you pay an amount of equal to its mana value.

When Volo enters, create Volo's Journal, a legendary colorless Book artifact token with hexproof and "Whenever you cast a creature spell, note one of its creature types that hasn't been noted for Volo's Journal."
, : Draw a card for each creature type noted for target permanent you control named Volo's Journal.
Choose a Background

As long as the top card of your graveyard is a creature card, this creature has the full text of that card and has the text ": Discard a card." (This creature has that card's name, mana cost, color, types, abilities, power, and toughness.)
: Discard a card.

: Add . Spend this mana only to cast an instant or sorcery spell or a kicked spell.

Flying, vigilance
Whenever you cast a spell with one or more targets, draw that many cards.

Flash
When this creature enters, counter target artifact or creature spell.

: Put this creature and each creature blocking or blocked by it on top of their owners' libraries, then those players shuffle.
: Target creature blocks this creature this turn if able.

As long as you control eight or more lands, this creature gets +1/+0 and can't be blocked.

Multikicker
Flying
When this creature enters, up to X target creatures gain flying until end of turn, where X is the number of times this creature was kicked.

Flying
Whenever one or more creatures you control with flying deal combat damage to a player, put a +1/+1 counter on each of those creatures and draw a card.