D&D 5E What is the best monster in 5th edition at being "Legendary"?

[Stalker0]

Legendary monsters hold a special place in 5th. Battles with such monsters are meant to be special, often boss battles that are the endings of arcs or even entire campaigns. Legendary monsters are supposed to provoke awe and dread, and a battle with one should feel like a truly epic moment.

So if you consider a combination of flavor (how does the monster feel, how does it affect the campaign, etc) and mechanics (how well does the monster handle a party of PCs, and how interesting does it make the fight), what do you think is best exemplar of the "legendary monster" in 5th edition?

 

[Lyxen]

I really like my bosses to be even more mythic than legendary, but in those published, some of the demon princes / arch devils are really interesting, especially the teleporting ones (since for me it recreates the danger and frustration of AD&D), and they usually have at least one or two powers in there that well match the nature of the beast, like the "Dance my puppet" or "Sow Discord" of Graz'zt.

 

[Tales and Chronicles]

The Drow Matron Mother and the Sibriex (with the added Flesh Warp features) are pretty terrifying

The new aspects of dragon gods from FtD are really cool, with the mythic template and all that.

 

[doctorbadwolf]

The best one I’ve used was a “chuul-drake matriarch”. Imagine tentacled drakes of various kinds, lead by a massive tentacles wyvern that had legendary actions to move all aberrations within 100ft closer to her, allow all chuul-drakes with 100ft to attack as a reaction, do a screech that did psychic and Thunder damage and summoned reinforcements over the next couple turns, and gained lair actions when she had enough allies within hearing of her, making the battle get harder as it went on.

She also had multiple bonus actions and reaction abilities, could eat a willing creature to regain HP, could grapple a creature with her tentacles, and had a poisoned tail barb like a wyvern.

It was epic, especially as a fight for level 8 PCs.

To me, leader legendary creatures are the best. A solo, I’d have to give defensive reactions and more legendary actions, as well as solid bonus actions, and when the group fights the ancient red dragon that the Kobold wizard is hunting, he will be mythic and will make an area his lair by being present. I may also make him so big they have to climb him, and some other buffs.

One thing I think legendaries need is 2+ reactions, or the ability to burn a LA to use a reaction ability even if you’ve already done so this round.

 

[Lyxen]

The Drow Matron Mother and the Sibriex (with the added Flesh Warp features) are pretty terrifying

I agree in terms of design, my only problem with the sibriex is that failing a save gets you a feature that can only be removed by a wish, which is for me way too strong a punishment for something that can be used at will and indeed even as a legendary action. Fighting one is almost a guarantee that you will have a group of adventurers that will look like deformed wretches until the end of the campaign, as a wish used there is not an "easy" use of the spell and you have 33% chance of never being able to use it again.

The new aspects of dragon gods from FtD are really cool, with the mythic template and all that.

These are cool, I agree.

 

[TheSword]

The dragons with the optional spellcasting rules are probably my favorite. Truly terrifying.

I havent read Fizbans but will see.

 

[doctorbadwolf]

The dragons with the optional spellcasting rules are probably my favorite. Truly terrifying.

I havent read Fizbans but will see.

I like to give really mythic dragons extra turns, where they can use movement and use wings and tail, and some of thier minor abilities.

When you combine that with legendary actions and spellcasting, !

 

[Tales and Chronicles]

I like to give really mythic dragons extra turns, where they can use movement and use wings and tail, and some of thier minor abilities.

When you combine that with legendary actions and spellcasting, !

One cool trick to make an epic dragon fight is to divide the beast into differents moving part, so each of its part has its own actions allotment.

ie: a ancient dragon fight would a be fight against, say,

• 1 large forelegs unit legs multiattacks claws and grapple and a 15 ft speed. Imune to mind affecting spells.
• 1 large hindlegs unit with a single attack that pushes and a 30 ft speed. Immune to mind affecting spells
• 1 huge body + head with a bite or breath attack and a speed of 0 ft. If the body falls to 0 hp, all other parts do too.
• 1 large tail with a tail slap that can prone and deal damage and a speed of 0 ft.
• 1 large wings unit with a wing attack that pushes and prone and a fly speed of 40 ft. Immune to mind affecting spells.

Give each of them an appropriate HP and AC amount, and you are all set.

 

[doctorbadwolf]

One cool trick to make an epic dragon fight is to divide the beast into differents moving part, so each of its part has its own actions allotment.

ie: a ancient dragon fight would a be fight against, say,

• 1 large forelegs unit legs multiattacks claws and grapple and a 15 ft speed. Imune to mind affecting spells.
• 1 large hindlegs unit with a single attack that pushes and a 30 ft speed. Immune to mind affecting spells
• 1 huge body + head with a bite or breath attack and a speed of 0 ft. If the body falls to 0 hp, all other parts do too.
• 1 large tail with a tail slap that can prone and deal damage and a speed of 0 ft.
• 1 large wings unit with a wing attack that pushes and prone and a fly speed of 40 ft. Immune to mind affecting spells.

Give each of them an appropriate HP and AC amount, and you are all set.

Yeah I did a similar thing with a huge construct recently.

This reminds me, why isn't the tail an AoE? It’s big, does a sweep. Even just moving should force saves against bludgeoning damage and being knocked prone.