When you create a new character, you can play as a Goblin. Goblin use their LOWEST stat, not their highest, to determine which goblin race-as-class-class they play.
If your Strength is the lowest, your play a Goblin Stabber. If your Dexterity is the lowest, you play a Goblin Guard. If your Wisdom is the lowest, you play a Goblin Catalyst. If your Charisma is the lowest, then you're a Filth Goblin.
d6 health dice
can wear leather armor
saves as Thief
You deal +1 damage for sneak attacks per level. You get +1 to hit when you go for the crotch or the eyes. At level 2 level you can jump on a bigger enemy's back and avoid it from attacking you before it knocks you off again, only works once per enemy. At level 3 level you can drink (and spit) poison into a creature's mouth or eyes to give it to them without damage to yourself. At level level 5 you gain a rat pet that can crawl on enemies to distract and bite or can spy on things for you.
At level 10 you must steal a human baby from its crib. You can now take its innocence and you can appear as a human child at will.
d8 health dice
can use anything you can hold or wear on your small body
saves as Fighter
You are the biggest and toughest goblin, and you know it. If you bully another goblin, destroy something of theirs or deal 1 damage in bruises to them, you get +2 AC for the rest of the day. At level 2 you can step in the way of an attack aimed at an ally, using your AC and health instead.
When using a spear against a larger target, add your level to hit. When using an axe or club against a target of roughly equal size to you, add your level to hit. You get +1 to save to avoid getting knocked out of the way by bigger fighters. At level 6 you can use a barrel as armor and roll into people to deal 1d6 damage as a charging attack- but you have to be fat.
At level 10, you become invited to become a guard for a goblin king. This gets you close enough to him to one day betray him and become goblin king yourself.
d4 health dice
cannot wear armor or shields
saves as Cleric, +1 vs explosions
You may conjure a blast of elemental energy (fire, ice, lightning) at will, deals 1d6 damage. Targets get save -1 per your Catalyst level for half damage. Each time you do this, get a Catalyst point.
If you have Catalyst points > your level roll a save vs magic or else take 1d6 damage of that element in an explosion radius centered on you.
At level 2 add +2 to all reaction checks with elemental creatures. At level 4 your elemental damage grows to 1d8 and you can sense elementals nearby. At level 7 you can chain your elemental blasts to targets near the first, but must roll a cataclysm save each time it chains. Once the chain starts, it won't stop until a save is made and you have to keep rolling cataclysm points.
At level 10, you will trap a serious elemental storm in a jar or urn like a wildfire, tsunami, blizzard, or lightning storm. If urn is opened or shattered, the storm is released. Only works once.
d8 health dice
cannot wear armor but can use any weapon
saves as Fighter, +2 vs disease
As long as you are covered in something foul smelling and disgusting, you get +1 AC against regular enemies, +2 AC against elves and those with sensitive noses, and +4 AC against bite attacks. Whenever you attack a foe with a rusted or shit-covered blade, they must save at -1 per filth goblin level or get a minor disease and take 1 damage from the infectious wound.
At level 3 enemies take 2 damage from failing your disease save. At level 4 you can now eat pond scum, slop, or poop to sustain yourself, and do not need to eat rations; you'll refuse to eat rations unless you are unable to get at your favorite filth. At level 8 you can jump inside of a gelatinous slime and use it as a mount, as it will refuse to digest you or anything you're touching.
At level 10, you become infected with a brand new disease that never existed before. It deals at least -1d8 damage to a specific stat and 1 level of level drain against those who catch it.