Changeling (This card is every creature type.)
: Fire-Belly Changeling gets +1/+0 until end of turn. Activate this ability no more than twice each turn.
"My ears say it hisses. My fingers say it burns."
—Auntie Wort
Target creature gets +2/+2 until end of turn. Clash with an opponent. If you win, that creature gets an additional +2/+2 and gains trample until end of turn. (Each clashing player reveals the top card of their library, then puts that card on the top or bottom. A player wins if their card had a higher converted mana cost.)
When Flamekin Harbinger enters the battlefield, you may search your library for an Elemental card, reveal it, then shuffle your library and put that card on top of it.
As an additional cost to cast this spell, sacrifice a Goblin.
Target creature gets -5/-5 until end of turn. Fodder Launch deals 5 damage to that creature's controller.
Leave it to a boggart to come up with a projectile as disgusting as it is deadly.
Flying
Whenever Galepowder Mage attacks, exile another target creature. Return that card to the battlefield under its owner's control at the beginning of the next end step.
When Giant Harbinger enters the battlefield, you may search your library for a Giant card, reveal it, then shuffle your library and put that card on top of it.
Create two 1/1 green Elf Warrior creature tokens. Clash with an opponent. If you win, those creatures gain deathtouch until end of turn. (Each clashing player reveals the top card of their library, then puts that card on the top or bottom. A player wins if their card had a higher converted mana cost. Any amount of damage a creature with deathtouch deals to a creature is enough to destroy it.)