The Speed Demon

Flying, trample
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.)
At the beginning of your end step, you draw X cards and lose X life, where X is your speed.

Waxen Shapethief

Flash
You may have this creature enter as a copy of an artifact or creature you control.
Cycling (, Discard this card: Draw a card.)

Mindspring Merfolk

Exhaust — , : Draw X cards. Put a +1/+1 counter on each Merfolk creature you control. (Activate each exhaust ability only once.)

Waxen Shapethief

Flash
You may have this creature enter as a copy of an artifact or creature you control.
Cycling (, Discard this card: Draw a card.)

Mindspring Merfolk

Exhaust — , : Draw X cards. Put a +1/+1 counter on each Merfolk creature you control. (Activate each exhaust ability only once.)

Fearless Swashbuckler

Haste
Vehicles you control have haste.
Whenever you attack, if a Pirate and a Vehicle attacked this combat, draw three cards, then discard two cards.

The Speed Demon

Flying, trample
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.)
At the beginning of your end step, you draw X cards and lose X life, where X is your speed.

Fearless Swashbuckler

Haste
Vehicles you control have haste.
Whenever you attack, if a Pirate and a Vehicle attacked this combat, draw three cards, then discard two cards.

Hydroid Krasis

When you cast this spell, you gain half X life and draw half X cards. Round down each time.
Flying, trample
Hydroid Krasis enters with X +1/+1 counters on it.

Primordial Hydra

Primordial Hydra enters with X +1/+1 counters on it.
At the beginning of your upkeep, double the number of +1/+1 counters on Primordial Hydra.
Primordial Hydra has trample as long as it has ten or more +1/+1 counters on it.

Unbound Flourishing

Whenever you cast a permanent spell with a mana cost that contains , double the value of X.
Whenever you cast an instant or sorcery spell or activate an ability, if that spell’s mana cost or that ability’s activation cost contains , copy that spell or ability. You may choose new targets for the copy.

Zaxara, the Exemplary

Deathtouch
: Add two mana of any one color.
Whenever you cast a spell with in its mana cost, create a 0/0 green Hydra creature token, then put X +1/+1 counters on it.

Gargos, Vicious Watcher

Vigilance
Hydra spells you cast cost less to cast.
Whenever a creature you control becomes the target of a spell, Gargos, Vicious Watcher fights up to one target creature you don’t control.

Mycoloth

Devour 2 (As this enters, you may sacrifice any number of creatures. This creature enters with twice that many +1/+1 counters on it.)
At the beginning of your upkeep, create a 1/1 green Saproling creature token for each +1/+1 counter on Mycoloth.

Siege Rhino

Trample
When Siege Rhino enters, each opponent loses 3 life and you gain 3 life.