Redcap Thief

When Redcap Thief enters, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Mountain

Molten Gatekeeper

Whenever another creature you control enters, Molten Gatekeeper deals 1 damage to each opponent.
Unearth {R} ({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.)

Pyrewild Shaman

Bloodrush — {1}{R}, Discard Pyrewild Shaman: Target attacking creature gets +3/+1 until end of turn.
Whenever one or more creatures you control deal combat damage to a player, if Pyrewild Shaman is in your graveyard, you may pay {3}. If you do, return Pyrewild Shaman to your hand.

Enterprising Scallywag

At the beginning of your end step, if you descended this turn, create a Treasure token. (You descended if a permanent card was put into your graveyard from anywhere.)

Dragon Fodder

Create two 1/1 red Goblin creature tokens.

Goblin Fireleaper

{1}{R}: Goblin Fireleaper gets +1/+0 until end of turn.
When Goblin Fireleaper dies, it deals damage equal to its power to target creature an opponent controls.

Goblin Blast-Runner

Goblin Blast-Runner gets +2/+0 and has menace as long as you sacrificed a permanent this turn.

Gut, True Soul Zealot

Whenever you attack, you may sacrifice another creature or an artifact. If you do, create a 4/1 black Skeleton creature token with menace that's tapped and attacking. (It can't be blocked except by two or more creatures.)
Choose a Background (You can have a Background as a second commander.)

Squee, the Immortal

You may cast Squee, the Immortal from your graveyard or from exile.

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.

Sardian Avenger

First strike, trample
Whenever Sardian Avenger attacks, it gets +X/+0 until end of turn, where X is the number of artifacts your opponents control.
Whenever an artifact an opponent controls is put into a graveyard from the battlefield, Sardian Avenger deals 1 damage to that player.