Drooling Ogre

Whenever a player casts an artifact spell, that player gains control of Drooling Ogre. (This effect lasts indefinitely.)

Soulsurge Elemental

First strike
Soulsurge Elemental's power is equal to the number of creatures you control.

Generator Servant

{T}, Sacrifice Generator Servant: Add {C}{C}. If that mana is spent on a creature spell, it gains haste until end of turn. (That creature can attack and {T} as soon as it comes under your control.)

Earth Elemental

Vexing Devil

When Vexing Devil enters the battlefield, any opponent may have it deal 4 damage to them. If a player does, sacrifice Vexing Devil.

Diamond Knight

Vigilance (Attacking doesn't cause this creature to tap.)
As Diamond Knight enters the battlefield, choose a color.
Whenever you cast a spell of the chosen color, put a +1/+1 counter on Diamond Knight.

Bomat Courier

Haste
Whenever Bomat Courier attacks, exile the top card of your library face down. (You can't look at it.)
{R}, Discard your hand, Sacrifice Bomat Courier: Put all cards exiled with Bomat Courier into their owners' hands.

Immersturm Raider

When Immersturm Raider enters the battlefield, you may discard a card. If you do, draw a card.

Scrapwork Mutt

When Scrapwork Mutt enters the battlefield, you may discard a card. If you do, draw a card.
Unearth {1}{R} ({1}{R}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Goro-Goro, Disciple of Ryusei

{R}: Creatures you control gain haste until end of turn.
{3}{R}{R}: Create a 5/5 red Dragon Spirit creature token with flying. Activate only if you control an attacking modified creature. (Equipment, Auras you control, and counters are modifications.)

Sparring Construct

When Sparring Construct dies, put a +1/+1 counter on target creature you control.

Battle-Mad Ronin

Bushido 2 (Whenever this creature blocks or becomes blocked, it gets +2/+2 until end of turn.)
Battle-Mad Ronin attacks each combat if able.

Mountain

Blood Knight

Hellspark Elemental

Trample, haste
At the beginning of the end step, sacrifice Hellspark Elemental.
Unearth {1}{R} ({1}{R}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Blood Servitor

When Blood Servitor enters the battlefield, create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this artifact: Draw a card.")

War Elemental

When War Elemental enters the battlefield, sacrifice it unless an opponent was dealt damage this turn.
Whenever an opponent is dealt damage, put that many +1/+1 counters on War Elemental.

Runed Servitor

When Runed Servitor dies, each player draws a card.

Fire Bowman

Sacrifice Fire Bowman: It deals 1 damage to any target. Activate only during your turn, before attackers are declared.

Frostling

Sacrifice Frostling: It deals 1 damage to target creature.

Reinforced Ronin

Haste
At the beginning of your end step, return Reinforced Ronin to its owner's hand.
Channel — {1}{R}, Discard Reinforced Ronin: Draw a card.