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In D&D 5e, Half-Dragon is a template (MM, 180) that can be applied to any beast, humanoid, or giant. When I applied the Red Dragon Wyrmling's dragon breath - which deals 7d6 fire damage in a cone - to a Raven (CR 0) it came out as CR 1/4 (according to the creating a monster section of the DMG).

Druids can Wild-shape into any creature CR 1/4 or lower, starting at 2nd level (or Circle of the Moon Druids can Wild-shape into CR 1 creatures).

This would mean a level 2 Druid can wild shape into a creature that can deal 7d6 fire damage in a cone, with a 1/3 chance of being able to reuse it every turn. This is more damage than any other class can deal at this level, even with max stats (eg. a fighter action surging [once per day] deals only a max of 4d6+10, approximately the same as this, which the druid can do infinite times in a day). So, can druids Wild Shape into beasts with the half-dragon template?

Akixkisu
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TheDragonOfFlame
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3 Answers3

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Players can't apply templates to creatures, nor can they assess CR. That's up to the DM.

You'd have to discuss this with your DM, and they'd likely (at the very least) tell you that you'd need to have seen a Half-Dragon Raven before you can do this. They might also disagree with your assessment of the CR, especially when it's a creature in the hands of a player. You've got no argument against it, since there's no printed statblock for a Half-Dragon Raven and the CR guidelines are explicitly meant to as guidelines and give the DM final control over the CR.

And, also relevant, this won't even work. Your Druid can't turn into flying creatures at level 2. You could probably turn into a Half-Dragon Rat if the DM lets you.

And the final thing; you say "7d6 almost infinitely" but you probably forgot that these CR 0 critters have only 1 hit point, so realistically you can do this once and then your wild shape ends and you take a full attack's worth of damage minus one point.

So really, it's something that required DM approval, they'd probably not let you do it, and even if they did you'd quickly find out that it's of fairly limited use.

Erik
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Half-dragons don't have a defined CR.

The one example in the MM, the half-dragon Veteran, is CR 5 and is explicitly based on a CR 3 Veteran.

The CR of a half-dragon-half-raven is not specified, though we can infer it would be higher than the CR of a raven.

The template does say that the CR can sometimes be left unchanged, if the creature is already an appropriately high CR for its size / breath weapon potency. Otherwise, "you" determine the CR by applying the guidelines in the Dungeon Master's Guide (which, note, is the Dungeon Master's Guide, so it's intended for use by the DM). So suppose you make a good-faith attempt to do that.

What should the CR be for a flying creature with 1 hit point and a 7d6 breath weapon? There's no precedent for that. The mismatch between its dinky AC 12 1hp frame and its great honking flamethrower throws the guidelines all out of whack. (Even calculating the "average" damage output of the attack is hard: a 24 damage AOE will end a lot of fights in round 1, so the recharge doesn't matter; if the bird has enough space to fly out of range while recharging, then the recharge really doesn't matter; etc.) The guidelines are just not written for this.

And this breaks the assumption that keeps Wild Shape under some kind of control: you can only turn into a beast, and beasts have a fairly narrow range of capabilities. They don't get spells or AOE attacks or teleportation or other craziness. They almost never get ranged attacks. They do sometimes get swimming or flight--and Wild Shape locks those creatures out until higher levels. Wild Shape is still very powerful for what you get, but the individual forms are supposed to be kind of boring.

Mark Wells
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  • It should be CR 1/4, according to the customizing a monster section of the DMG – TheDragonOfFlame Dec 02 '20 at 19:27
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    @TheDragonOfFlame No. You have read that section incorrectly. That section doesn't give hard rules for what CR is. It gives vague guidelines, and tells the DM to adjudicate for themselves. There's a lot of DM adjudication baked into 5e, and situations like this are exactly why. – Ben Barden Dec 02 '20 at 19:32
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    @TheDragonOfFlame "An appropriately equipped and well-rested party of four adventurers should be able to defeat a monster that has a challenge rating equal to its level without suffering any deaths." A party of 1st-level adventurers fighting four of these birds is going to die. – Mark Wells Dec 02 '20 at 19:38
  • @TheDragonOfFlame a half-dragon raven has an offensive CR of 11 (if I am reading the table right) and a defensive CR of 0, sugesting that its final CR is around 5. – Greenstone Walker Dec 02 '20 at 22:43
  • Heck a party of level 2 PCs vs 8 of these guys (approx CR 2), or a party of level 3 PCs vs 12 of these guys (approx CR 3), are ALSO going to get royally creamed. – Pat Dec 03 '20 at 01:42
  • @GreenstoneWalker Using the rule of thumb that AOE damage counts double, and assuming the breath weapon fires every turn, yes. That's questionable since it can't fire every turn--unless it kills everyone in round 1 and then the fight's over. So it's CR 11 if you're below about level 4, and then abruptly becomes CR 4 because you can survive the first strike. This nicely shows the limitations of CR as a measure of lethality. – Mark Wells Dec 03 '20 at 03:34
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The half-dragon raven is CR 3, so this won't work

It is true that

  • applying templates to Beasts and creating new monsters is the province of the DM,
  • beasts that are not directly from the Monster Manual require DM consent
  • the procedure on p. 274 of the DMG needs judgment, as formulas are not able to account for all the possible interactions
  • a normal wild shaping druid cannot transform into a flying creature

All of these are valid objections to the original poster's efforts to break the game with this combination. However, they are not needed.

Using the normal, unmodified calculation procedure, the CR of a half-dragon raven (or rat) is not 1/4, it is 3, and as such it will be out of reach of both a normal druid or a moon druid on level two.

Calculation

Here is the step-by-step calculation:

Raven: AC 12 hp +4 to hit Damage 1 piercing CR 0

Half Dragon Template adds : Fire Breath 15-foot cone 24 (7d6) DC 15 Dex save halves

For the purpose of determining effective damage output, assume the breath weapon hits two targets, and that each target fails its saving throw (DMG p. 280)

That is, the breath weapon is worth 48 Damage/round

DMG p. 274

CR 0: Armor Class <= 13 Hit Points 1-6

Defensive Challenge Rating: 0, since both AC and Hit Points fall into the CR 0 category.

CR 7: Attack Bonus +6, Damage/round 45-50, DC 15

If your monster's attack bonus is at least two points higher or lower than that number, adjust the challenge rating suggested by its damage output up or down by 1 for every 2 points of difference

Offensive Challenge Rating CR 6, since from the base of 7 for 48 Damage per round we deduct one point for the 2 point lower Attack bonus.

The monster's final challenge rating is the average of its defensive and offensive challenge ratings.

Average Challenge Rating: (0+6)/2 = 3

Nobody the Hobgoblin
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    I don't know what excactly you refer to. I do believe you cannot always trust CR calculations, but in this case, even the unadjusted calculation would block any abuse of the template. Can you be more specific? It seems nobody did check the claim that the resulting creature is 1/4. – Nobody the Hobgoblin Mar 01 '22 at 17:33
  • Thanks! The guidelines come out with a CR 3 creature, much more in line with the deadliness of the creature, and by normal guidance for CRs able to kill level one characters, as Mark suggests. I agree with everything he says in principle, but in this case the guideline seems to work pretty well. And would nip the druidic shenanigans in the bud. – Nobody the Hobgoblin Mar 01 '22 at 17:39
  • Other comments even make the point that the low hp and AC makes the creature very vulnerable. So the downsides still are real, and reduce the CR. I just think the whole argument of the original plan hinges of the creature just being CR 1/4, and it is not. – Nobody the Hobgoblin Mar 01 '22 at 17:50
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    Cool Cool. Just wanted to see if you had seen it :) – NotArch Mar 01 '22 at 17:57
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    Druid circles of the moon at max level can change to a CR 6 creature tho... – Rp_Master Mar 01 '22 at 18:33
  • Yessir. At that CR fire breath seems to be fine to me. If I'm not mistaken, the point of the original idea was to get access to it way early, when it would be overpowered. – Nobody the Hobgoblin Mar 01 '22 at 18:40
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    If I had to guess, the OP got the CR from taking a damage of 24 (i.e to only one creature) and dividing by 3 because of the recharge 5-6. That gives an average DPR of 8 or CR 1/2 for the offensive challenge rating. Not saying they were right, just trying to understand where their calculation came from. – smbailey Mar 01 '22 at 23:20
  • Excessively Minor Nitpick (that Changes Nothing): 3.5 x 7 x 2 = 49, not 48. Yes, floor(3.5 x 7) = 24, and 24 x 2 = 48, but for calculating average damage I don't think you should apply the floor function before multiplying by targets. – Richard Winters Mar 02 '22 at 06:55
  • :). The reason I used 24 is because the damage in the Fire Breath description is given as "Each creature in that area must make a DC 15 Dexterity saving throw, taking 24 (7d6) fire damage on a failed save", so 24 seems to be the default value to use. – Nobody the Hobgoblin Mar 02 '22 at 06:59
  • To explain myself, the reason I said that it was 1/4th is that the template rules say that the CR would be unchanged when using wyrmling breath. Obviously the calculations would say otherwise. This question was a bit of a ‘hack’ for a pro optimization (read cheating) one shot, so I was trying to figure out if by RAW it would work. – TheDragonOfFlame Mar 04 '22 at 03:21
  • Your calculations do not check, though, since the ability has a recharge. It should be dragon breath round one, then the rat or ravens base attack round two and three, averaged. Which would give damage of roughly 20. – TheDragonOfFlame Mar 04 '22 at 03:23
  • @TheDragonOfFlame: All dragon breath that I know of (including the one in the example for ancient black) do have some kind of recharge. I think in this case, you make an assumption that is not in the rules, and that led to your result. There is an explict statement how dragon breath is to be calculated, and it does not say anything about considering recharge. – Nobody the Hobgoblin Mar 04 '22 at 06:22
  • If you look at all the trait CR mods in the table, they just give an absolute directive how to modify damage. For example, Doppelgangers Ambusher increases the Attack Bonus by one. But it only works in the first round. Would you argue that because the average fight is 5 rounds, you should divide the effect by 5? The same logic applies for Dragon Breath - the numerical adjustment already considers that this is a nova effect in the first round and how dangerous it is. There is no dividing for averaging rounds to be done. – Nobody the Hobgoblin Mar 04 '22 at 06:31