Ogre Battledriver

Whenever another creature you control enters, that creature gets +2/+0 and gains haste until end of turn. (It can attack and {T} this turn.)

Storm Strike

Target creature gets +1/+0 and gains first strike until end of turn. Scry 1.

Hexgold Sledge

For Mirrodin!
When Hexgold Sledge enters, conjure a card named Goblin Gaveleer onto the battlefield.
Equipped creature gets +1/+0.
Equip {1}

Raid Bombardment

Whenever a creature you control with power 2 or less attacks, Raid Bombardment deals 1 damage to the player or planeswalker that creature is attacking.

Moria Marauder

Double strike
Whenever a Goblin or Orc you control deals combat damage to a player, exile the top card of your library. You may play that card this turn.

Goblin Morale Sergeant

Haste
Enlist
Whenever Goblin Morale Sergeant enlists a nontoken creature, you may conjure a duplicate of that creature into the top five cards of your library at random. The duplicate perpetually gets +1/+0 and gains haste.

Tectonic Hazard

Tectonic Hazard deals 1 damage to each opponent and each creature they control.

Rundvelt Hordemaster

Other Goblins you control get +1/+1.
Whenever Rundvelt Hordemaster or another Goblin you control dies, exile the top card of your library. If it's a Goblin creature card, you may cast that card until the end of your next turn.

Squee, Dubious Monarch

Haste
Whenever Squee, Dubious Monarch attacks, create a 1/1 red Goblin creature token that's tapped and attacking.
You may cast Squee, Dubious Monarch from your graveyard by paying {3}{R} and exiling four other cards from your graveyard rather than paying its mana cost.

Rebel Salvo

Affinity for Equipment (This spell costs {1} less to cast for each Equipment you control.)
Rebel Salvo deals 5 damage to target creature or planeswalker. That permanent loses indestructible until end of turn.

Melt Through

Melt Through deals 2 damage to any target. If it's a creature, it perpetually gains "As long as this creature is on the battlefield, damage isn't removed from it during cleanup steps."

Frantic Scapegoat

Haste
When Frantic Scapegoat enters, suspect it. (It has menace and can't block.)
Whenever one or more other creatures you control enter, if Frantic Scapegoat is suspected, you may suspect one of the other creatures. If you do, Frantic Scapegoat is no longer suspected.

Urabrask's Forge

At the beginning of combat on your turn, put an oil counter on Urabrask's Forge, then create an X/1 red Phyrexian Horror creature token with trample and haste, where X is the number of oil counters on Urabrask's Forge. Sacrifice that token at the beginning of the next end step.

Goblin Gang Leader

When Goblin Gang Leader enters, create two 1/1 red Goblin creature tokens.

Inescapable Blaze

This spell can't be countered.
Inescapable Blaze deals 6 damage to any target.

Furnace Reins

Gain control of target creature until end of turn. Untap that creature. Until end of turn, it gains haste and "Whenever this creature deals combat damage to a player or battle, create a Treasure token." (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Goblin Tunneler

{T}: Target creature with power 2 or less can't be blocked this turn.

Agatha's Soul Cauldron

You may spend mana as though it were mana of any color to activate abilities of creatures you control.
Creatures you control with +1/+1 counters on them have all activated abilities of all creature cards exiled with Agatha's Soul Cauldron.
{T}: Exile target card from a graveyard. When a creature card is exiled this way, put a +1/+1 counter on target creature you control.

City on Fire

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.)
If a source you control would deal damage to a permanent or player, it deals triple that damage instead.

Fugitive Codebreaker

Prowess, haste
Disguise {5}{R}. This cost is reduced by {1} for each instant and sorcery card in your graveyard. (You may cast this card face down for {3} as a 2/2 creature with ward {2}. Turn it face up any time for its disguise cost.)
When Fugitive Codebreaker is turned face up, discard your hand, then draw three cards.

Tomakul Phoenix

Flying, haste
When Tomakul Phoenix dies, it perpetually gets +2/+2.
At the beginning of combat on your turn, you may pay {X}{R}, where X is Tomakul Phoenix's power. If you do, return it from your graveyard to the battlefield.

Goblin Trashmaster

Other Goblins you control get +1/+1.
Sacrifice a Goblin: Destroy target artifact.

Shivan Devastator

Flying, haste
Shivan Devastator enters with X +1/+1 counters on it.

Burn Bright

Creatures you control get +2/+0 until end of turn.

Mountain

Tin Street Cadet

Whenever Tin Street Cadet becomes blocked, create a 1/1 red Goblin creature token.