5E: Monstrous Arthropods for Fifth Edition

[Cleon]

Okay, if the save-or-half does count as 150% damage then the Challenge Ratings are a bit different than 1/2/3 if I use the First Arrangement of Breath Weapon damages:

Dragonflies Combat Table

Type​	Defensive/Offensive CRs​	Bite​	Breath Weapon​
Black​	DCR 1/2; OCR 3 (DPR 16¼ of 15–26)​	+5, 6 (1d6 + 3) slashing​	6 (1d12) acid, DEX save DC 13 for ½​
Blue​	DCR 2; OCR 3 (DPR 18½ of 15–26)​	+5, 6 (1d6 + 3) slashing​	8 (1d6 + 1d8) lightning, DEX save DC 13 for ½​
Gold​	DCR 3; OCR 3 (DPR 23¼ of 15–20)​	+6, 7 (1d6 + 4) slashing​	10 (3d6) fire or poison, DEX save DC 14 for ½​
Green​	DCR 1; OCR 3 (DPR 17 of 15–26)​	+5, 6 (1d6 + 3) slashing​	7 (2d6) poison, DEX save DC 13 for ½​
Red​	DCR 2; OCR 3 (DPR 21 of 15–20)​	+6, 7 (1d6 + 4) slashing​	9 (2d8) fire, DEX save DC 14 for ½​
White​	DCR 1/4; OCR 2 (DPR 14¾ of 9–14)​	+5, 6 (1d6 + 3) slashing​	5 (1d10) cold, DEX save DC 13 for ½​

So we'd be talking:

Gold Dragonfly CR 4
Red Dragonfly CR 3
Blue Dragonfly CR 3
Green Dragonfly CR 2
Black Dragonfly CR 2
White Dragonfly CR 1

If we instead have it possess a "all or nothing" breath weapon that does no damage on a miss, the Challenge Ratings go back to their original values:

Gold Dragonfly DPR 18, CR 3
Red Dragonfly DPR 16½, CR 3
Blue Dragonfly DPR 14½, CR 2
Green Dragonfly DPR 13½, CR 2
Black Dragonfly DPR 13, CR 1
White Dragonfly DPR 12, CR 1

Hardly surprising, since that was the assumption I used with the CR Calculator.

 

[Casimir Liber]

Is it agreeable?

yep

I'd go with save =half and have the CRs ranging from 1 (white) to 4 (gold)

 

[Cleon]

yep

I'd go with save =half and have the CRs ranging from 1 (white) to 4 (gold)

Works for me.

Have updated the Mystaran Dragonflies collected post.

I fancy giving them another Save Proficiency and am leaning towards CON.

We also need to decide on Skills. I'm thinking Perception might be enough.

Next is Special Traits. I'd like to trim them down from the rather overburdened Odonatid I came up with, but would be OK giving them Expert Aerialist and Keen Sight.

Should we give it the Dodging Flight in Reactions?

That'd match the original flavour text about them darting around in the air.

The original monster had a special trait of its Breath Weapon that opponents engaged in melee with it are unable to make saving throws for half damage.

Will we be doing something with that? Maybe if an opponent is targeted with both its Bite and Breath Multiattack, it has disadvantage on its saving throw against the Breath Weapon?