Let's Read the 4e Monster Manual/Vault: Marilith
This is part of a series! Go here to see the other entries.
I think I’ve finally figured out what distinguishes a humanoid from a magical beast in 4e. Does it have hands? If it does it’s a humanoid, if it doesn’t it’s a magical beast.
That’s the only explanation that makes sense for why a Marilith is a Large Elemental Humanoid (demon), despite being a six-armed lady with the lower body of a snake. With succubi having become devils (more on that later), mariliths have the distinction of being the most human-looking of demons. Some people even find them sexy. Yes, I’m talking about you, dear Monster Musume fans.
These demons have been a part of the game for a long time, and are iconic enough to exist both in the Monster Manual and on the Monster Vault. The two versions are mostly identical, but we’ll still look at them separately here.
Mariliths are among some of the most intelligent demons at Int 14, losing only to the Glabrezu in that field. Their appetite for destruction takes on a more refined shape than usual: they are obsessed with martial skill, so they look for tough opponents to fight and tend to take their gear as trophies. They store these trophies in secret stashes on the Abyss or in the world, presumably to prevent other demons from stealing them. It seems to me that looting such a stash is a sure way to incur their wrath, which makes it a nice hook. Yuan-Ti who turn to demonology are big fans of mariliths.
Mariliths are usually armed with six swords, one for each hand, though you could mix and match the weapons if you wanted. In previous editions the weapons would sometimes take a backseat to their many spell-like abilities, but here they are definitely the main event.
Both versions of the Marilith are Level 24 Elite Skirmishers: they’re pretty high up in the demonic hierarchy, such as it is. Their skill list backs this up: they’re trained in Perception, Bluff, Insight, Intimidate, and Stealth. Yes, mariliths can socialize if they feel the need. Their descriptions in other editions tend to describe them as excellent tactitians and commanders, and this definitely fits this incarnation as well.
Marilith (Monster Manual)
The MM Marilith has 440 HP, Darkvision, and Variable Resistance 20 (switchable 3x/encounter). They move at Speed 8.
Their basic attack is a scimitar, which is quite weak due to the math bug but has the High Critical property. Their most commonly used attack is Shroud of Steel, which allows them to make two scimitar attacks and use the other weapons to parry, granting itself a +4 bonus to AC for a turn.
Whenever an adjacent enemy misses the marilith with a melee attack, it can make a free scimitar attack against then. And twice per encounter (once at the start, once after being bloodied) they can perform the Weapon Dance, which allows them to make six scimitar attacks, shifting 1 square between each one.
Marilith (MV)
As stated earlier, the MV Marilith is very similar to the MM one. It has 436 HP instead of 440 and slightly different defenses, but retains the extensive skill list.
The main changes are in its attacks. The damage on the basic scimitar attack has been fixed, but it no longer has High Critical. Shroud of Steel now gives it a +6 to AC. It is otherwise identical.
Tactics and Encounters
Fighting a Marilith is much like fighting a blender. Ranged attacks are much safer than melee combat against them, but they’re fast, smart and will have backup from other demons when encountered. You could give it some out-of-combat rituals or abilities that allow it to prepare the terrain in advance, adding obscuring or blocking features that limit the PC’s ability to stay away and attack it from range. Or perhaps it just chooses a battlefield that already has all of that and baits the PCs into it.
The sample encounter in the MM is level 23, a marilith and four hezrou. The toad goons are just the thing to keep the fighters occupied while their boss slithers towards the squishies.