Platypi Stats

[Arkhios]

So...Because of reasons, my common-law wife would want a platypus for her character, either as a mount or as a familiar. Given that a real platypus is actually the size of a small cat, I'm forced to make a statblock from ground up. And to make things worse, normal platypi do not have stats either.

What I'm looking for here, is actual design help with the little beastie (though one could argue platypi were aberrations, due to how bizarre creatures they are!)

For a giant Platypus I'm aiming for up to CR 1/4 Beast, so that it could be an option for a Beastmaster Ranger, should that become relevant. Up to size large, but most likely only as big as medium.

Additionally, I would want to make stats for a regular platypus, which is likely Tiny, as cats are.

Common features would be that they have venomous spurs, they should be quick swimmers, but relatively slow at walking on land. Also being able to hold breath for a long time would be relevant.

TIA!

[TheTeaMustFlow]

Why does it have to be a giant platypus? Cat-size seems more appropriate for a familiar.

I'd just take the Cat statistics, replace the movement with 30ft land, 40ft swim, give it hold breath, and change the claw to a bite,

[Arkhios]

Why does it have to be a giant platypus? Cat-size seems more appropriate for a familiar.

I'd just take the Cat statistics, replace the movement with 30ft land, 40ft swim, give it hold breath, and change the claw to a bite,

Because I was requested both a regular platypus suitable as a familiar and one that would be suitable as a mount. Tiny, regular platypus is the easy one to create, I agree, but the giant version is not.
At minimum, it should be at least medium sized, but I suppose a mutated or altered in other ways could be even large. But I'd say that's absolute maximum size.

IIRC, Platypus' bill is soft and rubbery. It's not suitable for a bite attack. However, as mentioned, they have sharp spurs, which are also poisonous.

[digiman619]

Also worth noting is that platypi are poisonous.

[Belac93]

Also worth noting is that platypi are poisonous.

I think that's only the males.

[Arkhios]

I think that's only the males.

This is true. However for the sake of game, that is also largely irrelevant. If platypi are poisonous, even if it was males only, it doesn't have to be scientifically 100% accurate when we make their game stats.
The species being poisonous is a defining trait, so it should in my opinion be implemented on them.

No point of making two different blocks when only difference is poisonous or not.

EDIT: My common-law wife redefined her hopes for getting a mountable platypus, which could be a mutation between a crocodile and a platypus. The setting I'm designing the creature for does indeed allow mutations so it should be no-issue.

I came up with this iteration by combining the stats of a cat and a crocodile, and calculating their numeric values to averages of the two. Surprising enough, simply the average of CR 0 and CR 1/2 is exactly 1/4. Now I'm not certain this is how you should do it by RAW, but it works as a guideline at least.

Platydile
Medium beast, unaligned
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Armor Class 12 (natural armor)
Hit Points 11 (2d8+2)
Speed 30 ft., swim 30 ft.
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STR 9 DEX 13 CON 12 INT 3 WIS 11 CHA 6
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Senses passive Perception 10
Languages --
Challenge 1/4 (50 XP)
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Hold Breath. The platydile can hold its breath for 15 minutes.

ACTIONS
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Bite. Melee Weapon Attack: +3 to hit, one target.
Hit: 3 (1d4 + 1) piercing damage, and the target must make a DC 11 Constitution saving throw, taking 3 (1d6) poison damage on a failed save, or half as much damage on a successful one.

[Arkhios]

...as for the regular platypus, how does this sound to you?

Platypus
Tiny beast, unaligned
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Armor Class 12
Hit Points 4 (1d4+2)
Speed 20 ft., swim 30 ft.
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STR 3 DEX 15 CON 12 INT 3 WIS 11 CHA 6
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Senses passive Perception 10
Languages --
Challenge 0 (10 XP)
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Hold Breath. The platypus can hold its breath for 15 minutes.

ACTIONS
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Spurs. Melee Weapon Attack: +0 to hit, one target.
Hit: 1 piercing damage, and the target must make a DC 10 Constitution saving throw, taking 3 (1d6) poison damage on a failed save, or half as much damage on a successful one.


Scientific fact: Platypus poison is not fatal to humans, but it is painful enough to warrant the poison damage.