Recurrent NPC escapes

[citabogue]

My group consists of 5 5th level players (cleric, druid, sorcerer, barbarian and fighter).

Iam gonna make a sub-boss monster who is stalking on the group probly using invisibility or even the border ethereal plane. Its main role is to stalk on them and keep the main boss informed of their progress, strengths and weaknesses and sometimes interfere to put traps and aid other NPC's in combat. When he gets involved in combat he's gonna try to use spells from afar (haven't decide his school of magic yet) and try to escape when he gets in danger.

I would like ideas of how he could escape combat.

1st ideas :
-Etherealness (easy but 7th level spell against a party of 5th level characters)
-Plane shift (same problem)
-Invisibility (too easy to counter?)

PS : The campaign plays in the underdark. The sub-boss may be a spellcaster builded on a drider's body but that's not certain yet.

[leogobsin]

Honestly, Invisibility would probably do it. I don't know that there's actually that many ways to counter invisibility at a low level; there's Faerie Fire but if a creature goes invisible at the start of its turn and then moves (if you want to make them more slippery maybe give them the ability to Dash as a bonus action) aiming is gonna be kind of a crapshoot. Another option would be Blink: cast it when they get low on health and run while the party can't touch them (you can probably fudge the rolls for whether or not to shift to the Ethereal if need be).

[Quoxis]

Honestly, Invisibility would probably do it. I don't know that there's actually that many ways to counter invisibility at a low level; there's Faerie Fire but if a creature goes invisible at the start of its turn and then moves (if you want to make them more slippery maybe give them the ability to Dash as a bonus action) aiming is gonna be kind of a crapshoot.

- „see invisibility“ is a 2nd level spell available to bards, sorcerers and wizards of class levels 3 and higher
- invisibility doesn’t make you invulnerable or in-attackable, it imposes disadvantage on attacks (and spells that require line of sight don’t work - AOE spells work unhindered), so if the monster doesn’t have incredible AC, the PCs can still hit it, and even if it dashes they can do the same and follow it, unless...
- the monster needs a high stealth skill to actually benefit from invisibility, and i‘d say give it the chance to both become invisible AND take the hide action on the same turn, otherwise it’s just awkward („i can’t see it, but i know it’s there!“ - „Well ****, now it’s gone“).

Other than that:
- give it plenty of hp so it’s not affected by a well-rolled or upcast sleep spell, which is AOE and doesn’t require line of sight
- another spell that could work: rope trick, a 2nd level spell that lets you create an impenetrable extradimensional space that’s only accessible via a rope. If your monster has anything to do with spiders, that’s a flavorful and mechanically sound way of disappearing - give it a climb speed, allow it to get rid of the rope (so that it’s not followed) as a bonus or free action (technically it’s an interaction with an object) and don’t make the spell obvious enough to be identified by your players - it‘ll look like the baddie just climbed out of sight and vanished, but it’s RAW legal.

[Unoriginal]

Just remember to play fair: if they catch the sub-boss, your PCs can kill them.

I'd say Misty Step could be useful to escape.

[Vessyra]

Dimension door.

Something that could be done is to decide that the tunnel that the party is in is actually within 400 feet of a second seperate tunnel, meaning that the villain could D-door between to different tunnels, with only 400 feet+ teleports allowing accesses between the two tunnels. (Or a lot of mining tools)

The fact that two tunnels just happen to be within 400 feet of each other might be a hard coincidence to swallow, however, depending on how expansive the under dark is in your world.

[citabogue]

Thanks for the ideas, i'll def look into these options.

[Lunali]

One thing to consider, if you do use a spell as a means of escape, make him a sorc with subtle spell. If you don't, every time he tries it after the first (and possibly even then) you'll have to worry about counterspell.

[JackPhoenix]

A succubus. Not really an opponent for level 5 PCs, but good spy, and could be annoying. Shapechanging, can escape to Ethereal at will, tough enough to survive 1 round of incoming attacks. Charms may cause trouble, if you want, give her some more spellcasting, focused more on debuffs, control and illusions than damage.

The difficulty isn't in fighting her, but in catching her and forcing her to fight in the first place. She may even use her charms on other NPCs to fight for her.

[Davrix]

I cannot stress enough though like someone else said. Play fair. If the party outsmarts you and he's in a corer. Dont pull the Dm card and he gets away anyway.

That being said depending on the level of campaign someone might of made a clone for him.