Nine lives

The guardian cat

Not long ago, I created an NPC for my level 3 D&D party to encounter. The NPC is a little kitty in a basement beneath an abandoned tower full of magical treasures. As soon as the party began to take any items from the basement, the cat turned on them, swiping its little claws at the ankles of the daring adventurers. Two floating weapons assaulted the party together with the cat to prevent the party from stealing anything. The weapons were relatively easy to dispose of, but the cat just would not die: Every time someone struck a killing blow, the cat just reappeared, bigger and stronger.

By its ninth live, the cat was the size of a ferocious tiger.

Below, the stat block for the guardian cat. Also available as org and pdf. Thanks to Dungeon Dad for the inspiration.

Guardian Cat

Tiny beast, unaligned


Armour Class 12

Hit points 2 (1d4)

Speed 40 ft., climb 30 ft.

STR DEX CON INT WIS CHA
3 (-4) 15 (+2) 10 (+0) 3 (-4) 12 (+1) 7 (-2)

Condition Immunities charmed, frightened

Skills Perception +3, Stealth +4

Senses passive Perception 13

Languages

Challenge 5 (1,800 XP)


Keen Smell. The guardian cat has advantage on Wisdom (Perception) checks that rely on smell.

Dutiful. The guardian cat is ordered to protect something valuable belonging to its master. It will never leave its position, nor will it attack, unless it is attacked first, or someone other than its master tries to take something from the room it guards. If a fight breaks out, it will not pursue any attackers who try to leave, and will return to its initial spot, licking its wounds.

Alert. As soon as a fight breaks out with the guardian cat, its master is notified.

Nine Lives. The guardian cat has nine lives, represented by the nine stripes on its back. Each time it is reduced to 0 hit points, up to the ninth time, it is instantly reborn stronger than before and loses one stripe. It reappears in the same spot as before with full hit points, and all conditions except grappled and restrained are removed.

With each rebirth, the guardian cat grows in size. On its 3rd life, it becomes a Small creature. On its 5th life, it becomes a Medium creature. On its 8th life, it becomes a Large creature.

With each rebirth, add 3 (1d6) hit points to the guardian cat’s maximum. Starting at its 7th life, add 5 (1d8) hit points.

With each rebirth, the guardian cat’s Dexterity is increased by 1, and its Strength by 2.

Each day, the guardian cat regains a life and reduces in size and strength.

Find below a handy table.

Life HP Size AC Strength Dexterity Special
1st 2 Tiny 12 3 (-4) 15 (+2) Claws: 4 (1d4 + 2),
            Bite: 8 (1d10 + 2)
2nd 5 Tiny 13 5 (-3) 16 (+3)  
3th 8 Small 13 7 (-2) 17 (+3) Claws: 7 (2d4 + 3)
4th 11 Small 14 9 (-1) 18 (+4) Bite: 16 (2d10 + 4)
5th 14 Medium 14 11 (+0) 19 (+4) Pounce
6th 18 Medium 15 13 (+1) 20 (+5) Claws: 11 (3d4 + 5)
7th 23 Medium 15 15 (+2) 21 (+5) Bite: 23 (3d10 + 5)
8th 28 Large 16 17 (+3) 22 (+6) Growl
9th 33 Large 16 19 (+4) 23 (+6) Claws: 14 (4d4 + 6),
            Bite: 30 (4d10 + 6)

Pounce. Starting at its 5th life, the guardian cat has become big enough to pounce its enemies. If the guardian cat moves at least 20 feet straight toward a creature and then hits it with a claw attack on the same turn, that target must succeed on a DC 13 Strength saving throw or be knocked prone. If the target is prone, the guardian cat can make one bite attack against it as a bonus action.


Actions

Multiattack. The guardian cat makes two claw attacks.

Claws. Melee Weapon Attack: +DEX to hit, reach 5 ft., one target. Hit: 2 (1d4) + DEX slashing damage. Every third life, the damage increases by 2 (1d4).

Bite. Melee Weapon Attack: +DEX to hit, reach 5 ft., one target. Hit: 6 (1d10) + DEX piercing damage. On its 4th, 7th and 9th life, the damage increases by 6 (1d10).

Growl. Starting at its 8th life, the guardian cat can let out a fierce and terrifying growl. Everyone within 10 feet of the guardian cat must succeed on a DC 13 Wisdom saving throw or be frightened of the cat for 1 minute. A frightened target can repeat the saving throw at the end of each of its turns, with disadvantage if the guardian cat is visible to the target, ending the effect on itself on a success.