Wild Cantor

({R/G} can be paid with either {R} or {G}.)
Sacrifice this creature: Add one mana of any color.

Fyndhorn Elves

Tinder Wall

Defender (This creature can't attack.)
Sacrifice this creature: Add {R}{R}.
{R}, Sacrifice this creature: It deals 2 damage to target creature it's blocking.

Skirk Prospector

Birds of Paradise

Gilded Goose

Flying
When this creature enters, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")
{1}{G}, {T}: Create a Food token.
{T}, Sacrifice a Food: Add one mana of any color.

Elvish Spirit Guide

Exile this creature from your hand: Add {G}.

Mishra's Bauble

{T}, Sacrifice this artifact: Look at the top card of target player's library. Draw a card at the beginning of the next turn's upkeep.

Simian Spirit Guide

Manamorphose

Add two mana in any combination of colors.
Draw a card.

Pyretic Ritual

Llanowar Elves

Rite of Flame

Add {R}{R}, then add {R} for each card named Rite of Flame in each graveyard.

Desperate Ritual

Add {R}{R}{R}.
Splice onto Arcane {1}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Elvish Mystic

Urza's Bauble

{T}, Sacrifice this artifact: Look at a card at random in target player's hand. You draw a card at the beginning of the next turn's upkeep.

Jeweled Amulet

{1}, {T}: Put a charge counter on this artifact. Note the type of mana spent to pay this activation cost. Activate only if there are no charge counters on this artifact.
{T}, Remove a charge counter from this artifact: Add one mana of this artifact's last noted type.

Orcish Lumberjack

{T}, Sacrifice a Forest: Add three mana in any combination of {R} and/or {G}.

Wild Growth

Enchant land
Whenever enchanted land is tapped for mana, its controller adds an additional {G}.

Goldhound

First strike
Menace (This creature can't be blocked except by two or more creatures.)
{T}, Sacrifice this creature: Add one mana of any color.

Minsc & Boo, Timeless Heroes

When Minsc & Boo enters and at the beginning of your upkeep, you may create Boo, a legendary 1/1 red Hamster creature token with trample and haste.
+1: Put three +1/+1 counters on up to one target creature with trample or haste.
−2: Sacrifice a creature. When you do, Minsc & Boo deals X damage to any target, where X is that creature's power. If the sacrificed creature was a Hamster, draw X cards.
Minsc & Boo, Timeless Heroes can be your commander.