Breaching Hippocamp

Flash (You may cast this spell any time you could cast an instant.)
When this creature enters, untap another target creature you control.

Wavebreak Hippocamp

Whenever you cast your first spell during each opponent's turn, draw a card.

Cobbled Lancer

As an additional cost to cast this spell, exile a creature card from your graveyard.
{3}{U}, Exile this card from your graveyard: Draw a card.

Chrome Steed

Metalcraft — This creature gets +2/+2 as long as you control three or more artifacts.

Bill Ferny, Bree Swindler

Whenever Bill Ferny becomes blocked, choose one —
• Create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")
• Target opponent gains control of target Horse you control. If they do, remove Bill Ferny from combat and create three Treasure tokens.

Surge Mare

This creature can't be blocked by green creatures.
Whenever this creature deals damage to an opponent, you may draw a card. If you do, discard a card.
{1}{U}: This creature gets +2/-2 until end of turn.

Phantom Steed

Flash
When this creature enters, exile another target creature you control until this creature leaves the battlefield.
Whenever this creature attacks, create a tapped and attacking token that's a copy of the exiled card, except it's an Illusion in addition to its other types. Sacrifice that token at end of combat.

Diamond Mare

As this creature enters, choose a color.
Whenever you cast a spell of the chosen color, you gain 1 life.