Standing about 4 feet 4 inches tall when upright, a Giant Rat walks with a hunched, sinewy frame built for both bursts of speed and narrow passages. Its lean body is covered in short, coarse fur that varies from grey-brown to dark rust. Its long tail aids balance when climbing or darting through cluttered terrain.

Despite their unsettling appearance, trained Giant Rats like Greg exhibit remarkable coordination, surprising strength for their size, and an odd curiosity about the world around them. They are agile survivors who adapt to any environment—from city sewers to battlefield trenches.

Size: Small

• You occupy a 5-ft space but can move through spaces occupied by any creature one size larger.

• You can share an ally’s space but cannot end your turn there unless the ally is prone or willing to lift you (DM’s discretion).

• Your carrying capacity and the weight you can push, drag, or lift are 3/4 that of a Medium creature (use normal Strength rules × 0.75).

Speed: 30 ft walking, 20 ft climbing.
Your tail and limbs are adapted to gripping rough surfaces.

Level-Scaling Additions

• Level 5+: Increase your climb speed to match your walking speed (30 ft).

• Level 9+: Gain a Burrow speed of 10 ft through loose soil or sand as you learn to dig shelters.

You have an exceptional sense of smell. You can detect faint odors, distinguish between individuals by scent, and sense nearby creatures through their trail. You gain Advantage on Wisdom (Perception) and Intelligence (Investigation) checks that rely on smell. You also can identify creatures, food, or materials by scent at DM discretion.

Life in sewers, dungeons, and the fringes of civilization has left you hardy and stubborn. Your digestive system laughs at spoiled meat, your lungs shrug at noxious fumes, and your body resists poisons that would fell less fortunate creatures.

Though small and often underestimated, your natural resilience makes you a reliable companion in any environment. You’re the kind of rat who emerges from battle messy, sweaty, but still standing, sometimes carrying a shard of the enemy’s armor as a trophy.

Mechanical Effects

• Resistance to poison damage.

• Advantage on Constitution saving throws vs. disease and poison condition.

• Immunity to natural spoiled food or nonmagical contamination.

• You automatically find edible scraps in barren environments (for yourself).

Level-Scaling Additions

• Level 3: Your survival instincts sharpen; you gain +1 to Constitution saving throws.

• Level 6: Your body adapts further to danger; your carrying capacity increases by +10 lbs, and you can survive brief exposure to extreme cold or heat without suffering environmental penalties (like exhaustion from mild exposure).

• Level 11: Your immunity grows subtle enhancements — you now add +2 to Constitution saving throws against disease or poison effects.

• Level 13: You can tolerate slightly magical spoiled food (like old alchemical ingredients) without penalty — DM discretion.

Your small, lithe frame and dexterous limbs make you surprisingly acrobatic. You can climb walls, leap across obstacles, and maneuver through spaces that would trap larger creatures. Your tail acts as a counterweight, and your paws are adapted for gripping surfaces.

While your movement may seem erratic, it often allows you to reach vantage points, escape danger, or retrieve items from hard-to-reach locations. Observers might marvel—or groan—at how he squeezes into tight corners or climbs surfaces like it’s second nature.

Mechanical Effects

• Climbing: You have a climb speed equal to your walking speed. You don’t need to make an ability check to climb vertical surfaces unless the DM rules it’s particularly slick or magical.

• Squeezing: You can move through a space that is one size smaller than you without penalty.

• Jumping: You gain a +2 bonus to Athletics or Acrobatics checks made to jump across gaps or onto surfaces.

Level-Scaling Additions

• Level 5: You learn to scurry faster and smarter; your jump distance increases by 50% (both long and high jumps).

• Level 9: Your climbing ability improves further. You can now climb upside down along ceilings or narrow ledges, making Acrobatics checks at DC 10 instead of DC 15.

• Level 12: Once per long rest, you can take the Dash action as a bonus action for 1 minute, representing a burst of frantic agility that lets you reach allies, loot, or advantageous positions quickly.

You have sharp teeth and surprisingly strong jaws for your size. You can bite foes to harass, distract, or nibble at unarmored areas, making a minor but reliable attack. Though small, your bites are agile and precise, often aiming for weak points or exposed skin.

Biting is quick and instinctive — perfect for hitting vulnerable spots or finishing off low-health enemies. Your opponents may underestimate you, which is exactly what you rely on.

Mechanical Effects

• Action: Make a melee weapon attack with your bite.

• Attack Bonus: Strength or Dexterity modifier + proficiency bonus (your choice, depends on focus).

• Damage: 1d4 piercing damage.

• Range: Melee, 5 ft.

Special: You may make a Disarming Bite once per short or long rest. On a hit, the target must succeed on a DC 12 Strength saving throw or drop a held item (DM discretion).

Level-Scaling Additions

• Level 3: Bite damage increases to 1d6 piercing.

• Level 5: Bite range increases to 10ft.

• Level 7: Disarming Bite DC increases to 14.

• Level 9: You can now use this attack as a bonus action.

• Level 11: You gain Improved Precision: add your Dexterity or Strength modifier (whichever you’re using) twice to a bite attack once per turn (represents a well-aimed gnash).

• Level 14: Bite damage increases to 1d12 piercing.

• Level 17: Once per long rest, your bite counts as a critical on a roll of 19–20, representing peak rat ingenuity.

You instinctively stay close to your companions, alert to danger and ready to intervene in subtle ways. Even if you cannot speak, your presence is reassuring: a nudge, a squeak, or a quick scuttle can help an ally regain composure or keep their footing.

Though your methods may be unconventional, they are effective. You rarely take the spotlight but your loyalty and quick reactions ensure that your allies benefit from your attention.

Mechanical Effects

• While within 10 ft of an ally, you can grant a +1 bonus to their saving throws (Constitution, Dexterity, or Wisdom, player’s choice).

• This bonus applies automatically while you are conscious and in range.

• You can use your reaction to move up to 10 ft toward an ally who is about to fail a saving throw, granting them advantage on that save.

Level-Scaling Additions

• Level 4: Allies’ saving throw bonus increases to +2 while in range.

• Level 7: Your reaction ability can now be used twice per long rest.

• Level 11: The range of your passive support bonus increases to 15 ft.

• Level 14: The reaction effect now allows the ally to reroll once per use if they fail the saving throw.

• Level 18: Allies within range gain +2 AC for 1 round once per long rest when you are within 10 ft and conscious (represents your instinctive blocking and alertness).

You uses your small size, speed, and sheer audacity to distract enemies. Darting unpredictably between foes and allies, you squeak, wave your tail, and generally causes chaos on the battlefield. Some foes are so confused or irritated by your antics that they lose track of their original target.

This is not mind control — just the effect of being an annoying, persistent pest. You are often puts himself at risk to save his friends, earning their admiration (or eye rolls).

Mechanical Effects

• Action: You may target 1 creature within 15 ft that you can see.

• The target makes a Wisdom saving throw (DC = 8 + your proficiency bonus + Dexterity modifier).

• On a failed save:

  • It must target you with its next attack (melee or ranged) if able.

  • It has disadvantage on attack rolls against other creatures until the end of its next turn.

• On a successful save:

  • The creature is briefly annoyed: it has disadvantage on its next attack roll, but continues its previous target normally.

Recharge: Once per short or long rest.

Level-Scaling Additions

• Level 8: The save DC increases by +1.

• Level 12: You can target 2 creatures instead of 1, but only one can fail the save automatically — the other makes a Wisdom saving throw normally.

• Level 15: The distraction lasts until the end of the creature’s next turn instead of just until the start of your next turn.

You have spent years turning ruin into resource. Your eye and paws miss little: a bent pin becomes a lockpick, a scrap of wire mends a strap, and a dropped potion rarely goes unnoticed. Your instincts for useful materials and desperate improvisation allow you to keep the party going when luck runs thin.

In the heat of action you have developed a knack for salvaging success out of failure. When a companion’s motion falters or tools slip, you nudge, squeak, or otherwise intervene with uncanny timing, sometimes turning disaster into a workable setback.

You are not a master craftsman, but you are an expert scavenger. Between fights you root through debris and broken gear with purpose; in combat you are a living, squeaky contingency plan.

Mechanical effects

Your loyalty and experience have grown. You no longer just scurry about collecting scraps — you actively look out for your companions. You know when danger is about to strike, and your small size allows you to slip into positions others can’t reach to draw attacks or provide support.

Whether it’s positioning yourself to draw attention, squeaking loudly to startle foes, or using your agility to interfere with enemy strikes, you are now an active guardian. You may be tiny, but your presence is noticed — and sometimes dreaded — by those who attack your friends.

Mechanical Effects

Defender Reaction:
When a creature within 5 feet attacks a target other than you, you can use your reaction to impose disadvantage on that attack. You must be able to see the attacker.

Protective Dash:
If the attack still hits, you can immediately move up to 10 feet toward the attacker as part of the same reaction, representing your scrappy counter-positioning.

Healing Inspiration (Once per Short Rest):
When you reduce a creature to 0 HP (any enemy), you or an ally within 10 ft gains temporary hit points equal to your Constitution modifier + your proficiency bonus.

Level-Scaling Additions

• Level 11: You may use Defender Reaction twice per short or long rest, allowing you to cover multiple attacks per encounter.
• Level 14: Temporary hit points from Healing Inspiration increase by +2 per ally within 10 ft, rewarding clever positioning in group fights.
• Level 17: You gain Improved Guardian Reflexes: When you use Defender Reaction to impose disadvantage, the target’s attack automatically fails if your roll to contest it exceeds theirs by 5 or more (represents peak rat combat intuition).

Years of scurrying, digging, and exploring have transformed you into a master of the underground. You can slip through narrow passages, hide beneath the dirt, and emerge where enemies least expect. Your movements are silent but precise, letting you set up clever attacks, rescue allies, or escape dangerous situations.

You may be small, but your mastery over tunnels and the terrain gives you a surprising tactical edge. The party quickly notices that when you vanish into the ground, you’re not gone — you’re preparing your next move.

Mechanical Effects

Burrow Mastery:

• Your movement speed increases by 5 ft.

• You gain a burrow speed equal to half your walking speed.

• Difficult terrain composed of dirt, sand, rubble, or loose earth no longer costs extra movement.

Burrow Hide (Action):

• You can use an action to dig yourself partially into the ground, becoming heavily obscured until you move or attack.

• This can be used to avoid attacks, set up ambushes, or escape line-of-sight temporarily.

Extended Breath:

• You can hold your breath for up to 10 minutes, representing stamina and adaptation to underground conditions.

Level-Scaling Additions

• Level 15: Burrow Hide now grants advantage on Dexterity (Stealth) checks while partially burrowed.
• Level 17: Burrow speed increases to full walking speed, letting you move underground as quickly as above ground. Burrow Hide allows allied creatures within 5 ft to gain half cover while you are partially burrowed.
• Level 20: You may use Burrow Hide as a bonus action instead of an action. You can remain heavily obscured while moving up to half your speed in burrowed terrain once per short rest.