Does unlimited Wild Shape make Circle of the Moon archdruids virtually unkillable?

Question

Page 67 of the PHB states that druids gain all the hit points of whatever creature they become when using Wild Shape, and when that shape drops to 0hp, only the excess damage carries over to the druid's original form.

Since archdruids (level 20) can use Wild Shape an unlimited number of times per day, and dismissing Wild Shape is a bonus action, could an archdruid just keep transforming into a high-HP Earth elemental over and over during a battle?

If they get near 0hp while in elemental form, they can dismiss it as a bonus action, then re-apply it as an action, all in one turn, and never take "excess damage", so their druid form would never be harmed.

Am I misunderstanding something about how hit points work between these forms, or is a level 20 Circle of the Moon druid virtually immune to all but the most insane damage spikes?

Answer 1

No.

A druid can only wildshape on his turn. So, while he can apply unlimited hitpoints to his form by wildshaping every turn, he cannot prevent you from dealing damage when it isn't his turn. If the druid is knocked out of his form (reduced to 0 hp), the first thing that happens is the excess damage carries over. But now he's essentially vulnerable until his turn. That's where the real damage comes in. You can think of wildshape as a regenerative shield of hit points.

Party Versus NPC Archdruids

There are a multitude of ways to "beat" the druid, just like any other encounter. Use your wits, bargain, stealth, combat, etc etc. Those tools are ALWAYS available. Your DM should be ready for you to avoid combat if you wish.

Party Versus PC Archdruids

If you're talking about PC vs PC combat, there are also a plethora of spells that can assist in killing the druid. For instance, if the druid has less than 100 HP in wildshape OR not, a Warlock can cast Power Word: Kill, and the druid simply dies. No save, just dead. That's just one spell. There are tons of others. A Druid can't wildshape if they're incapacitated. They, again, also can't wildshape unless it is their turn, so plan your heavy attacks accordingly. When a druid is knocked out of form, they are vulnerable, so maximize your damage in that time or make that vulnerability last longer with controlling spells. Any damage that exceeds a druid's wildshape form is applied to the druids regular form. Druids are very good at having health, so find a way to attack them in ways where health isnt the primary objective. Use conditions, spell effects, and any means to hinder the druid and he/she shouldn't be that tough of a fight.

Specialization

DnD 5e rewards specialization. An Archdruid specializes in wildshape to effectively gain temporary hitpoints among other combat abilities. It's the whole point of a wildshaping druid. Being a brown bear is cool, but when you can wildshape into one and get its free hitpoints, it becomes a big deal. That's largely what wildshaping druids are meant to do, so it only makes sense that it gets ridiculously good at it at level 20. All classes have a 20th level ability they get that helps them be even more specialized. It's a reward for forgoing multiclassing. Therefore, it should feel hard to deal damage to an Archdruid. But it's not impossible.

Answer 2

A 20th level Druid is hard to kill, but far from impossible

High level characters are supposed to be strong. But a moderately optimized 11th level party should be able to take him down. It will be long, and quite boring, but it can be done.

How to do it

There is a limit to these seemingly unlimited hit points, and you can use that. The Druid can only have one bonus action per round, so every damage you do above 126 HP (Earth Elemental) in one turn is substracted from the Druid's base hit points. You can wear him down slowly, as the damage output of an Earth Elemental is quite low.

A 5th level Monk with Stunning Fist can deny even that one bonus action.

The Banishment spell can be readied to send the Druid to another plane, where it cannot use any actions. Bring it back to a place where he is surrounded by the other party members, also readying some attacks.

There are many options, you just have to be creative.

Answer 3

Any level 20 character should be VERY difficult to kill. A level 20 fighter would have a LOT of magical equipment and surprises. The same goes for a level 20 rogue. Level 20 wizards are pretty much reality warpers when played intelligently.

Druids, like wizards, are less reliant on equipment thematically, so you most likely will not have to deal with that (Most of the equipment I want as a druid is something that aids my spellcasting or that I can wear while wild shaped (which limits things considerably), anything else will be better utilized by the martial characters). It's not much different from a wizard getting an "always on" shield spell (easily achievable as a level 20 wizard) or a demiplane or clone. If you are not level 20 you should have a VERY difficult time fighting a level 20.

A lot of the above answers also forget that a level 20 druid can cast spells while they are shapeshifted, and spend spell slots to heal themselves. This makes them a viable tank (with greater focus on soaking damage with hitpoints instead of avoiding it through ac, which is usually low for level 20, especially when compared to a fighter in enchanted plate with an enchanted shield).

Answer 4

Wildshape is suspended in an anti-magic field

Cast anti-magic field and duke it out with melee. No wildshape unlimited healing for the druid. You do have a fighter in your party right?

Yeah so the wizard is going to be in trouble. On the other hand, the wizard can concentrate on parrying, etc, while the fighter cuts down the druid.

If you happen to have arcane archer's imbue arrow ability available (not clear from the question) it would make setting this up far easier. Who wouldn't make anti-magic field arrows if given the chance? It's also a good excuse to use an arrow on your teammate.

On the other hand, even after they nerfed shrink item I can still come up with a couple of ways of doing stupidly huge damage at level 17.

Answer 5

Planeshift the druid to the abyss, or the plane of fire, not instant death, but pretty close.(wizard, warlock, sorcerer, bard, cleric)

Better yet, Planeshift them to a demi plane you created that is full of magic symbols set to go off with a wide variety of damaging spells to instantly kill the druid.(wizard)

True polymorph the druid into an animal, or into an object. Wait one hour, without losing your concentration and the druid is essentially dead.(wizard,warlock, bard)

Place a devouring bag over the druids head. (Rogue, fighter, barbarian, ranger, druid)

Polymorph the druid into a turtle (or another small slow animal), stick him into a bag of holding and he will die after 15? minutes, depends on the animal you polymorph him into, done animals can hold their breath for a long time. (Wizard, sorcerer, bard)

Burst damage kill him, (hasted vengence/rogue asssain, auto crits and does 300+ damage in the first round)