Are there any official CR 8 beasts that are not dinosaurs, for the purpose of the Polymorph spell?

Although the party wizard has had a wand of polymorph since finding it in a hand-converted U3: The Final Enemy (before the release of Ghosts of Saltmarsh), she has typically used it defensively, turning enemies into slugs and such. Only recently has she begun to use it offensively. After fighting some carnivorous apes, she turned the 7th-level barbarian in the party into a CR 7 Giant Ape when he was low on HP.

Per the description of the polymorph spell:

The new form can be any beast whose challenge rating is equal to or less than the target’s (or the target’s level, if it doesn’t have a challenge rating).

As a result of that battle, the party has leveled up, and the wizard can now polymorph the barbarian into a beast of CR 8.

Unfortunately, I know of only one CR 8 creature that is a beast – the Tyrannosaurus rex. While RAW there is no restriction on using polymorph to achieve forms that the character has not seen before, it would harm the verisimilitude of my game, in which none of the characters have even heard of dinosaurs.

Do any official published products include CR 8 beasts that are not dinosaurs?

Embiggening monster for higher CR for Polymorph [Homebrew]

Although the party wizard has had a wand of polymorph since finding it in a hand-converted U3 (before the release of Ghosts of Saltmarsh) she has typically used it defensively, turning enemies into slugs and such. Only recently has she begun to use it offensively. After fighting some carnivorous apes, she turned the party member L7 Barbarian into a CR7 Giant Ape when he was low on hp.

Polymorph

The new form can be any beast whose challenge rating is equal to or less than the target’s (or the target’s level, if it doesn’t have a challenge rating).

As a result of that battle, the party has leveled, and the wizard can now polymorph the barbarian into a beast of CR8.

Unfortunately, I know of only one CR8 creature that is a beast – the Tyrannosaurus rex. While RAW there is no restriction on using polymorph to achieve forms not seen before, it would harm the verisimilitude of my game, in which none of the characters have even heard of dinosaurs.

However, if the wizard knows that Giant Apes exist, I think it is plausible for her to reason that there must be even-more-giant Apes, and simply try to make the barbarian bigger the next time she casts the spell.

Thus, I am considering allowing a larger version of a Giant Ape, in which some of the stats have been embiggened to achieve the low end of CR8. I am interested in responses to this as a homebrew concept.

Useful answers could include:

  1. Information about other publicly-available non-dinosaur CR8 beasts
  2. Conformation or refutation of my assumption that such ‘variable size’ polymorphing is not allowed RAW
  3. Conformation or refutation of my assumption that so long as the new form is a variation of an official one and the CR is calculated correctly, there are unlikely to be balance issues.
  4. Confirmation or refutation that I have calculated CR correctly for the larger version (below).

CR7 Giant Ape
AC12, 157hp (15d12+60), At. 2 @ +9 to hit, 3d10+6 dmg, ADPRH 45

CR8 Proposed Giant Ape [all other stats as RAW Giant Ape]
AC13, 168hp (16d12+64), At. 2 @ +9 to hit, 3d12+6 dmg, ADPRH 51

CR7 Giant Ape Calculation
Hp 146-160 = CR6, AC is more than two below 15, adjust DCR -1 to 5
DPR 45-50 = CR7, to hit is more than two above +6, adjust OCR +1 to 8
Average CR 6.5, round to CR7

CR8 Proposed Giant Ape Calculation
Hp 161-175 = CR7, AC is two below 15, adjust DCR -1 to 6
DPR 51-56 = CR8, to hit is more than two above +6, adjust OCR +1 to 9
Average CR 7.5, round to CR8

When you learn True Polymorph, do you learn about every creature in existence?

When a wizard learns true polymorph, do they also learn about every creature in existence? Since the spell says the new form can be a creature of any kind you choose, it seems to me that this would mean they must have gained some knowledge about every creature in existence.

Or can you only turn into creatures that you have encountered "in your lifetime"?

How strong can someone make a Level 1 fighter, in Pathfinder, excluding Polymorph spells that change their body to another creature type?

It’s a classic trope in fiction, the "not so great" heroic character is going up against a foe they have no business trying to defeat and one (or more) of their allies that are a bit more powerful do a little something here, a little nudge there, and now the would-be hero is performing feats they never would have been able to do on their own.

What, in your estimation, would be the way to go about showing this sort of trope in a game like Pathfinder 1e? Defensive buffs out the wazoo are all well and good, but their low HD is also something to keep in mind, as Con buffs will be less effective. To ensure that the illusion is kept up as well, they’ll need to stay as their original race, no True Polymorphing them into a dragon or whatnot.

Dragon Change Shape feature vs Draconic Polymorph

I was curious about how the differences for a True Dragon using it’s natural Change Shape feature vs the Draconic Polymorph spell.

The Change Shape feature (text from Roll20 Compendium, Adult Gold Dragon) says this:

Change Shape: The Dragon magically polymorphs into a Humanoid or beast that has a Challenge rating no higher than its own, or back into its true form. It reverts to its true form if it dies. Any Equipment it is wearing or carrying is absorbed or borne by the new form (the dragon’s choice). In a new form, the Dragon retains its Alignment, Hit Points, Hit Dice, ability to speak, Proficiencies, Legendary Resistance, Lair Actions, and Intelligence, Wisdom, and Charisma scores, as well as this action. Its Statistics and capabilities are otherwise replaced by those of the new form, except any Class Features or legendary Actions of that form.

The Draconic Polymorph spell description (text from D&D Tools) says this:

As polymorph, except as follows: The assumed form can have no more Hit Dice than you have, to a maximum of 20 Hit Dice. Your Strength and Constitution in the new form are above the average for the race or species into which you transform; your Strength is the average for the creature +8, and your Constitution is the average for the creature +2.

So, I have a couple questions about this:

Damage: Does a dragon using the Change Shape feature only revert to it’s true form if it takes enough damage to kill said true form, or might it revert to true form if it takes enough damage to kill it’s assumed form?

Time Limit: Draconic Polymorph calls out ’10 minutes/level’ as the limit for maintaining an assumed form. Is the natural Change Shape unlimited in time?

If a creature dies when under the effect of a polymorph ability, does it ever revert to its true form?

Say a creature has polymorphed itself. For instance, a dandasuka using its Change Shape ability. If it dies, will it naturally revert to its true form? If so, when? I don’t see any info about this in the Polymorph trait’s rules.

If there aren’t any cut-and-dry rules about this, does any official literature suggest one way or another?

D&D 5e How to “properly” use polymorph?

I’m a new player trying to learn more and how the spells really work besides any game.

I was in a session, and occasionally a player used the "true polymorph" spell on a teammate to make it into a Planetar, and our DM said the spell only changes the player’s body so he would have no weapon (long sword) not even his characteristic as: Angelic Weapons, Divine Awareness, Innate Spellcasting and his Healing Touch. My question is, how to use the spell correctly? Can I use all of your skills and actions, including legendary actions? Can I use everything listed on the monster sheet? And another, if I transform myself permanently, can I level up and progress? From what I understood about the spell you can become a creature and play with everything and only what is described the creature sheet.

Being a new player, I always like to argue about and find out how my and other player’s actions really would work.

Can Polymorph be cast on a Familiar? [closed]

What a creature can be polymorphed into depends on the creature’s level or CR, of which a familiar has neither. Unless you use the CR of the form the familiar has taken. Or, as a spirit that takes the form of a creature, is a familiar a shapechanger and therefore not a valid target for the spell? If you can polymorph a familiar, is it still unable to attack?

True Polymorph interaction with Find Steed

Find Steed (p240 PHB) States:

When the steed drops to 0 hit points, it disappears, leaving behind no physical form. You can also dismiss your steed at any time as an action, causing it to disappear. In either case, casting this spell again summons the same steed, restored to its hit point maximum.

If I were to cast True Polymorh (p283 PHB) on the steed and wait the full duration to make it permanent, would the steed return when summoned as the original steed or as the new creature it was polymorphed into?

What is the meaning of ‘permanent’ in description of True Polymorph?

Following on from this question: Can I True Polymorph a goblin into adamantine (and then forge him into a sword?)

Casting True Polymorph on an unwilling creature (relevant parts included only):

You transform the creature into a different creature…or into an object.The transformation lasts for the duration, or until the target drops to O hit points or dies. If you concentrate on this spell for the full hour, the transformation becomes permanent. An unwilling creature can make a Wisdom saving throw, and if it succeeds, it isn’t affected by this spell.

Creature into Creature: The target assumes the hit points of its new form, and when it reverts to its normal form, the creature returns to the number of hit points it had before it transformed. If it reverts as a result of dropping to O hit points, any excess damage carries over to its normal form. As long as the excess damage doesn’t reduce the creature’s normal form to O hit points, it isn’t knocked unconscious.

Creature into Object: If you turn a creature into an object, it transforms along with whatever it is wearing and carrying into that form. The creature’s statistics become those of the object, and the creature has no memory of time spent in this form, after the spell ends and it returns to its normal form.

The consensus seems to be that if the creature fails the Wisdom save, you can transform it into a weak creature like a slug or an object like a cup, and can then wait for 61 minutes concentrating on the spell, then stamp on the item and kill it, permanently, because that was its new permanent form. But this seems terribly unbalanced, requiring a single wisdom save to be failed (and these can be influenced with features such as Heightened Spell and Magical Ambush) to kill any creature which can be polymorphed, no matter its stats. This also seems to make True Polymorph a better version of Power Word Kill (if delayed and requiring a save) since it is completely uncapped by health, only by Wisdom save proficiency, as well as including many other functions. This makes it seem unlikely this is the correct interpretation of True Polymorph since it renders another (already weak, for that level) spell almost entirely pointless.

I presumed the spell to be saying that after one hour of concentrating on it, the polymorphed form no longer needs to be concentrated on and could last forever, but will still revert back to the original form if reduced to 0 HP, as described in the linked question where the creature (polymorphed into crafting materials) was cut apart. This seems to make much more sense and retains balance.

Which interpretation is correct? Does the ‘permanent’ section overrule the ‘transforms back if reduced to 0 hit points’ part?